@article{sheoran_boland_thornton_bochinski_clarke_2023, title={Enhancing ionic conductivity in polymer melts results in smaller diameter electrospun fibers}, volume={123}, ISSN={["1077-3118"]}, url={https://doi.org/10.1063/5.0162384}, DOI={10.1063/5.0162384}, abstractNote={Chemically compatible additives were utilized to increase the ionic conductivity of polyethylene melts. When subjected to unconfined electrospinning, a predictable and significant decrease in the resultant fiber diameter with enhanced melt conductivity was observed. This generalized approach was confirmed for viscous melts, varying in conductivity over five orders of magnitude and viscosity 5×, from multiple commercial polyethylene formulations with various additives. These experimental results are connected to theory for the relevant length scales of capillary length, jet spacing, and jet radius. In particular, jet radius scales as conductivity to the −1/4 power. Fitting experimental fiber radius vs ionic conductivity data results in a similar power law exponent (−0.29). This trend, occurring at orders of magnitude higher viscosity and six orders of magnitude lower conductivity, is similar to results from needle-based, solution phase electrospinning, suggesting the generality of the effect. The connection between larger length scales, such as the distance between jets and the thickness of the film at the plate edge, and fluid properties (surface tension, viscosity, and conductivity) is also discussed.}, number={7}, journal={APPLIED PHYSICS LETTERS}, author={Sheoran, N. and Boland, B. and Thornton, S. and Bochinski, J. R. and Clarke, L. I.}, year={2023}, month={Aug} } @article{sheoran_boland_thornton_bochinski_clarke_2021, title={Increasing ionic conductivity within thermoplastics via commercial additives results in a dramatic decrease in fiber diameter from melt electrospinning}, volume={9}, ISSN={["1744-6848"]}, url={http://dx.doi.org/10.1039/d1sm01101d}, DOI={10.1039/d1sm01101d}, abstractNote={Role of conductivity and viscosity in determining jet size and fiber diameter in melt electrospinning is explored by new data and application of theory. Increasing conductivity via an additive leads to a large fraction of sub-micron diameter fibers.}, journal={SOFT MATTER}, publisher={Royal Society of Chemistry (RSC)}, author={Sheoran, Neelam and Boland, Brent and Thornton, Samuel and Bochinski, Jason R. and Clarke, Laura I.}, year={2021}, month={Sep} } @article{fontecha_mahn_bochinski_clarke_2022, title={Tracking the complete degradation lifecycle of poly(ethyl cyanoacrylate): From induced photoluminescence to nitrogen-doped nano-graphene precursor residue}, volume={195}, ISSN={["1873-2321"]}, DOI={10.1016/j.polymdegradstab.2021.109772}, abstractNote={Poly(ethyl cyanoacrylate) (PECA) is a commercial polymer which degrades easily at temperatures between 150 - 200 °C via an unzipping reaction where volatile monomer is produced. In this report, the complete moderate-temperature degradation lifecycle is delineated, which also includes formation of a carbonaceous by-product where the ester side groups are lost and ring formation between the backbone and cyano side group occurs. Degradation-induced photoluminescence is observed at an intermediate point where the remaining PECA (or re-polymerized oligomers) has sp3 carbons but sp2-carbon-containing clusters of the by-product that will ultimately form aromatic structures are also present. This observation supports the hypothesis that degradation-induced photoluminescence in polymers, which has been observed widely, is connected to the formation of such sp2 containing clusters, and that this process is relatively independent of the original polymer chemistry, as PECA dominantly degrades through a mechanism distinctly different than the thermo-oxidative cascade associated with many thermoplastic materials. As degradation further advances, a residue of approximately 8% of the original mass is produced which is no longer photoluminescent and can ultimately transform into nitrogen-substituted nano-graphene. Observing the entire lifecycle further solidifies the previously-proposed connection between degradation-induced luminescence in polymers and photoluminescence in hydrogenated amorphous carbon. The low degradation temperature of PECA also provides a bridge between classic polymer degradation and waste-to-graphene strategies that generally involve much more aggressive processing.}, journal={POLYMER DEGRADATION AND STABILITY}, author={Fontecha, Daniela and Mahn, Chelsea and Bochinski, Jason R. and Clarke, Laura I}, year={2022}, month={Jan} } @article{huang_firestone_fontecha_gorga_bochinski_clarke_2020, title={Nanoparticle-based photothermal heating to drive chemical reactions within a solid: using inhomogeneous polymer degradation to manipulate mechanical properties and segregate carbonaceous by-products}, url={https://doi.org/10.1039/C9NR07401E}, DOI={10.1039/C9NR07401E}, abstractNote={Nanoparticle-based photothermal heating degrades polymer from the inside-out, creating pockets of depolymerized material around each nanoscale heating site.}, journal={Nanoscale}, publisher={Royal Society of Chemistry (RSC)}, author={Huang, Honglu and Firestone, Gabriel and Fontecha, Daniela and Gorga, Russell E. and Bochinski, Jason R. and Clarke, Laura I.}, year={2020} } @article{firestone_huang_bochinski_clarke_2019, title={Photothermally-driven thermo-oxidative degradation of low density polyethylene: heterogeneous heating plus a complex reaction leads to homogeneous chemistry}, volume={30}, url={https://doi.org/10.1088/1361-6528/ab3bc0}, DOI={10.1088/1361-6528/ab3bc0}, abstractNote={Photothermal heating from embedded nanoparticles, a process whereby visible light is converted into heat resulting in a high temperature in each particle’s immediate vicinity, was utilized to degrade low density polyethylene (LDPE) via thermo-oxidation. The spatially-varying steady-state photothermal temperature field is a potential mechanism by which ambient light (e.g. sunlight) could be used to drive chemical reactions within solid materials and may result in a non-uniform pattern of products, an advantage or disadvantage depending on application. Novel approaches to control polymer degradation are of interest because of the goal of remediating plastic waste, including autonomous means to minimize its effect when unconfined in the environment. For thermoplastic auto-oxidation, heterogeneous degradation would likely enhance deleterious micro-fragmentation however, the multi-step, multi-site nature of the reaction mitigated the temperature non-uniformity. A photothermally-heated LDPE nanocomposite with silver nanoparticle and cobalt-stearate additives showed degradation, characterized by ultraviolet–visible and Fourier-transform infrared absorption spectroscopy, electron microscopy, and mechanical testing, nearly identical to that resulting from uniform conventional treatment at the same average temperature.}, number={47}, journal={Nanotechnology}, publisher={IOP Publishing}, author={Firestone, Gabriel and Huang, Honglu and Bochinski, Jason R and Clarke, Laura I}, year={2019}, month={Nov}, pages={475706} } @article{firestone_bochinski_meth_clarke_2018, title={Facile measurement of surface heat loss from polymer thin films via fluorescence thermometry}, volume={56}, ISSN={["1099-0488"]}, DOI={10.1002/polb.24571}, abstractNote={ABSTRACTQuantitative determination of heat loss and transport within complex systems having inhomogeneous temperatures and several different components is important for applications ranging from electronics to solar cells. An approach and material system to study heat transport within and heat loss from polymer thin films is presented. In a thin film configuration with a cylindrical heating source, the theoretical solution for temperature as a function of radial position can be determined from fundamental principles. Use of embedded fluorescent molecules as temperature probes and manipulation of the relative location of heating and thermometry light sources allows experimental measurements of temperature versus position within the plane of the film. For a large range of practical cases, the exact theoretical solution can be well‐approximated by a single term, which enables a fit to experimental data, and subsequent determination of either the heat loss coefficient at the film's surface or the material's effective thermal conductivity. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 643–651}, number={8}, journal={JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS}, author={Firestone, Gabriel and Bochinski, Jason R. and Meth, Jeffrey S. and Clarke, Laura I.}, year={2018}, month={Apr}, pages={643–651} } @article{dong_firestone_bochinski_clarke_gorga_2017, title={In situ curing of liquid epoxy via gold-nanoparticle mediated photothermal heating}, volume={28}, DOI={10.1088/1361-6528/aa521b}, abstractNote={Metal nanoparticles incorporated at low concentration into epoxy systems enable in situ curing via photothermal heating. In the process of nanoparticle-mediated photothermal heating, light interacts specifically with particles embedded within a liquid or solid material and this energy is transformed into heat, resulting in significant temperature increase local to each particle with minimal warming of surroundings. The ability to use such internal heating to transform the mechanical properties of a material (e.g., from liquid to rigid solid) without application of damaging heat to the surrounding environment represents a powerful tool for a variety of scientific applications, particularly within the biomedical sector. Uniform particle dispersion is achieved by placing the nanoparticles within solvent miscible with the desired epoxy resin, demonstrating a strategy utilizable for a wide range of materials without requiring chemical modification of the particles or epoxy. Mechanical and thermal properties (storage modulus, Tg, and degradation behavior) of the cured epoxy are equivalent to those obtained under traditional heating methods. Selective curing of a shape is demonstrated within a liquid bath of epoxy, where the solid form is generated by rastering a spatially confined, photothermal-driving light beam. The non-irradiated regions are largely unaffected and the solid part is easily removed from the remaining liquid. Temperature profiles showing minimal heating outside the irradiated zone are presented and discussed.}, number={6}, journal={Nanotechnology}, publisher={IOP Publishing}, author={Dong, Ju and Firestone, Gabriel E and Bochinski, J R and Clarke, L I and Gorga, R E}, year={2017}, month={Jan}, pages={065601} } @article{maity_wu_tracy_clarke_bochinski_2017, title={Nanoscale steady-state temperature gradients within polymer nanocomposites undergoing continuous-wave photothermal heating from gold nanorods}, volume={9}, ISSN={["2040-3372"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000407812000028&KeyUID=WOS:000407812000028}, DOI={10.1039/c7nr04613h}, abstractNote={Anisotropically-shaped metal nanoparticles act as nanoscale heaters via excitation of a localized surface plasmon resonance, utilizing a photothermal effect which converts the optical energy into local heat.}, number={32}, journal={NANOSCALE}, publisher={Royal Society of Chemistry (RSC)}, author={Maity, Somsubhra and Wu, Wei-Chen and Tracy, Joseph B. and Clarke, Laura I. and Bochinski, Jason R.}, year={2017}, month={Aug}, pages={11605–11618} } @article{viswanath_maity_bochinski_clarke_gorga_2016, title={Enhanced Crystallinity of Polymer Nanofibers without Loss of Nanofibrous Morphology via Heterogeneous Photothermal Annealing}, volume={49}, ISSN={["1520-5835"]}, DOI={10.1021/acs.macromol.6b01655}, abstractNote={Poly(ethylene oxide) electrospun nanofibers with a low concentration of embedded gold nanoparticles (AuNP) were subjected to postfabrication annealing via photothermal heating from the nanoparticles. The results, including nanofibrous mat morphology, crystallinity fraction as a function of annealing time and modality, and average crystallite size, were compared with that for conventional heating at the same average temperature. Maximum crystallinity is achieved more quickly under photothermal heating, and higher maximum crystallinity values, approaching the theoretical maxima for an entangled polymer (∼80%), are obtained. Photothermal heating better preserves the unique nanostructured morphology of the nanofibrous mat whereas significant fiber thickening and loss of porosity occur under conventional annealing treatment. With photothermal heating, heat may be predominantly applied within amorphous material within the fiber, which provides energy for the amorphous chains to reorient and then possibly crysta...}, number={24}, journal={MACROMOLECULES}, author={Viswanath, Vidya and Maity, Somsubhra and Bochinski, Jason R. and Clarke, Laura I. and Gorga, Russell E.}, year={2016}, month={Dec}, pages={9484–9492} } @article{abbott_maity_burkey_gorga_bochinski_clarke_2014, title={Blending with Non-responsive Polymers to Incorporate Nanoparticles into Shape-Memory Materials and Enable Photothermal Heating: The Effects of Heterogeneous Temperature Distribution}, volume={215}, ISSN={["1521-3935"]}, DOI={10.1002/macp.201400386}, abstractNote={Blending a shape‐memory polymer (SMP) (e.g., thermoplastic polyurethane) with an immiscible carrier polymer (e.g., poly(ethylene oxide) (PEO) or poly(vinyl alcohol) (PVA)) containing dispersed metal nanoparticles (AuNPs) is a simple approach to enable actuation via photothermal heating. For blends containing up to 90% carrier polymer, the shape‐memory capability can be thermally triggered either conventionally or utilizing internal heating via application of light that is resonant with the particle's surface plasmon resonance. When incorporating nanoparticles in this manner, neither chemical modification of the shape‐memory moiety nor solvation of the SMP is necessary. Actuation times are determined by the particular heterogeneous temperature distribution, which generally occurs under both conventional and photothermal heating methods, but with different spatial patterns. Blending an SMP with PEO containing AuNPs imposes a higher transition temperature (the melting point of PEO), enabling heat generated within the nanoparticle‐containing regions to equilibrate throughout the sample, resulting in performance under photothermal conditions comparable with that achieved in a conventional heating approach. SMP:PVA blends actuate at the SMP transition temperature and the response depends on the size of phase segregation between the PVA and SMP; when decreasing the characteristic size of the segregated regions, heat is efficiently transferred and optimal photothermal performance is observed. image}, number={23}, journal={MACROMOLECULAR CHEMISTRY AND PHYSICS}, author={Abbott, David B. and Maity, Somsubhra and Burkey, Mary T. and Gorga, Russell E. and Bochinski, Jason R. and Clarke, Laura I.}, year={2014}, month={Dec}, pages={2345–2356} } @article{thoppey_gorga_clarke_bochinski_2014, title={Control of the electric field-polymer solution interaction by utilizing ultra-conductive fluids}, volume={55}, ISSN={["1873-2291"]}, DOI={10.1016/j.polymer.2014.10.007}, abstractNote={Dramatically raising the conductivity of a polymer solution by using a salt additive allows control over the electric field-induced jet feed rate when electrospinning from an unconfined fluid without altering the applied voltage. As the solution conductivity increases, the flow rate drops by an order of magnitude. At a high voltage level and fluid conductivity value, the jets undergo a whipping instability over almost the entire path from the source to the collector experiencing only a negligibly short linear region which, along with the flow rate data, indicates that the jet narrows due to the high conductivity. Under these conditions, even while possessing relatively large individual jet feed rates, thin diameter nanofibers (200–300 nm) are readily produced. In contrast with other approaches to obtain narrow fibers from unconfined fluids (e.g., voltage reduction to control feed rate), here the fiber forming jets are present indefinitely. Continuous, scaled up nanofiber production rate of >125× over the traditional single needle electrospinning method is observed from the presence of multiple jets, each possessing a relatively high solution feed rate. These fundamental experiments reveal new pathways for exploring novel electrospinning configurations where the jet feed rate can be controlled by manipulating the solution conductivity.}, number={24}, journal={POLYMER}, author={Thoppey, N. M. and Gorga, R. E. and Clarke, L. I. and Bochinski, J. R.}, year={2014}, month={Nov}, pages={6390–6398} } @article{maity_wu_xu_tracy_gundogdu_bochinski_clarke_2014, title={Spatial temperature mapping within polymer nanocomposites undergoing ultrafast photothermal heating via gold nanorods}, volume={6}, ISSN={["2040-3372"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000345458200080&KeyUID=WOS:000345458200080}, DOI={10.1039/c4nr05179c}, abstractNote={Polarized fluorescence temperature measurements combined with direct detection of nanorod rotation within the polymer melt regions reveal the steady-state temperature gradient on the nanoscale.}, number={24}, journal={NANOSCALE}, author={Maity, Somsubhra and Wu, Wei-Chen and Xu, Chao and Tracy, Joseph B. and Gundogdu, Kenan and Bochinski, Jason R. and Clarke, Laura I.}, year={2014}, pages={15236–15247} } @article{wang_curtis_thoppey_bochinski_gorga_clarke_2014, title={Unconfined, melt edge electrospinning from multiple, spontaneous, self-organized polymer jets}, volume={1}, DOI={10.1088/2053-1591/1/4/045304}, abstractNote={Commercial grade polyethylene is melt electrospun from a thin film of unconfined molten polymer on a heated, electrically-grounded plate. Under the influence of an applied electric field, the melt spontaneously forms fingering perturbations at the plate edge which then evolve into emitting fiber-forming jets. Jet-to-jet spacing (∼5 mm), which is dependent on the applied voltage amplitude, is in agreement with estimates from a simple theoretical treatment. The broad applicability of the approach is verified by spinning a second polymer—polycaprolactone. In both cases, the fabricated fibers are similar in quality to those obtained under needle melt electrospinning; however for this method, there are no nozzles to clog and an enhanced production rate up to 80 mg min−1 is achieved from approximately 20–25 simultaneous parallel jets. The process of jet formation, effective flow rates, cone-jet diameters, as well as limits on jet density and differences with polymer type are compared with theoretical models. This particular approach allows facile, high throughput micro- and nano-fiber formation from a wide variety of thermoplastics and other high viscosity fluids without the use of solvents or the persistent issues of clogging and pumping that hamper traditional methods, resulting in mechanically strong meso-scale fibers highly desirable for industrial applications.}, number={4}, journal={Materials Research Express}, publisher={IOP Publishing}, author={Wang, Qingqing and Curtis, Colin K and Thoppey, Nagarajan Muthuraman and Bochinski, Jason R and Gorga, Russell E and Clarke, Laura I}, year={2014}, month={Nov}, pages={045304} } @article{maity_kozek_wu_tracy_bochinski_clarke_2013, title={Anisotropic Thermal Processing of Polymer Nanocomposites via the Photothermal Effect of Gold Nanorods}, volume={30}, ISSN={["1521-4117"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000315360400010&KeyUID=WOS:000315360400010}, DOI={10.1002/ppsc.201200084}, abstractNote={By embedding metal nanoparticles within polymeric materials, selective thermal polymer processing can be accomplished via irradiation with light resonant with the nanoparticle surface plasmon resonance due to the photothermal effect of the nanoparticles which efficiently transforms light into heat. The wavelength and polarization sensitivity of photothermal heating from embedded gold nanorods is used to selectively process a collection of polymeric nanofibers, completely melting those fibers lying along a chosen direction while leaving the remaining material largely unheated and unaffected. Fluorescence‐based temperature and viscosity sensing was employed to confirm the presence of heating and melting in selected fibers and its absence in counter‐aligned fibers. Such tunable specificity in processing a subset of a sample, while the remainder is unchanged, cannot easily be achieved through conventional heating techniques.}, number={2}, journal={PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION}, author={Maity, Somsubhra and Kozek, Krystian A. and Wu, Wei-Chen and Tracy, Joseph B. and Bochinski, Jason R. and Clarke, Laura I.}, year={2013}, month={Feb}, pages={193–202} } @article{roman_thoppey_gorga_bochinski_clarke_2013, title={Maximizing Spontaneous Jet Density and Nanofiber Quality in Unconfined Electrospinning: The Role of Interjet Interactions}, volume={46}, ISSN={["1520-5835"]}, DOI={10.1021/ma4013253}, abstractNote={The interplay between an applied electric field and fluid properties was studied for a polymer solution forming high quality nanofibers via electrospinning. Unconfined electrospinning—in which a fluid thin film or bath exposed to an electric field spontaneously generates many parallel fiber-forming jets—is a practical approach to achieving a high fabrication rate of quality nanofibers as compared to traditional single-needle electrospinning. The density of fiber-forming jets is controlled by surface tension effects at the lowest applied voltages but by jet-to-jet interactions as the voltage amplitude is increased, resulting in an intermediate operating voltage level at which jet number is maximized. This general result is applicable to electric-field-driven fluid instabilities in a wide range of systems. The optimal voltage level occurs when interjet interactions begin to solely determine the characteristic jet spacing, and in this regime, compression of the cone-jet slightly chokes the feed rate, allowin...}, number={18}, journal={MACROMOLECULES}, author={Roman, Michael P. and Thoppey, Nagarajan M. and Gorga, Russell E. and Bochinski, Jason R. and Clarke, Laura I.}, year={2013}, month={Sep}, pages={7352–7362} } @article{viswanath_maity_bochinski_clarke_gorga_2013, title={Thermal Annealing of Polymer Nanocomposites via Photothermal Heating: Effects on Crystallinity and Spherulite Morphology}, volume={46}, ISSN={["1520-5835"]}, DOI={10.1021/ma401855v}, abstractNote={Metal nanoparticles embedded within polymeric systems can act as localized heat sources, facilitating in situ polymer processing. When irradiated with light resonant with the nanoparticle’s surface plasmon resonance (SPR), a nonequilibrium electron distribution is generated which rapidly transfers energy into the surrounding medium, resulting in a temperature increase in the immediate region around the particle. This work compares the utility of such photothermal heating versus traditional heating in gold nanoparticle/poly(ethylene oxide) nanocomposite films, crystallized from solution and the melt, which are annealed at average sample temperatures above the glass transition and below the melting point. For all temperatures, photothermally annealed samples reached maximum crystallinity and maximum spherulite size faster. Percentage crystallinity change under conventional annealing was analyzed using time–temperature superposition (TTS). Comparison of the TTS data with results from photothermal experiments...}, number={21}, journal={MACROMOLECULES}, author={Viswanath, Vidya and Maity, Somsubhra and Bochinski, Jason R. and Clarke, Laura I. and Gorga, Russell E.}, year={2013}, month={Nov}, pages={8596–8607} } @article{thoppey_gorga_bochinski_clarke_2012, title={Effect of Solution Parameters on Spontaneous Jet Formation and Throughput in Edge Electrospinning from a Fluid-Filled Bowl}, volume={45}, ISSN={["1520-5835"]}, DOI={10.1021/ma301207t}, abstractNote={The process of edge electrospinning relies on forming electric-field-induced instabilities (i.e., jets) in a polymer solution bath which act as sources for nanofiber production. As such, it depends...}, number={16}, journal={MACROMOLECULES}, author={Thoppey, Nagarajan M. and Gorga, Russell E. and Bochinski, Jason R. and Clarke, Laura I.}, year={2012}, month={Aug}, pages={6527–6537} } @article{maity_bochinski_clarke_2012, title={Metal Nanoparticles Acting as Light-Activated Heating Elements within Composite Materials}, volume={22}, DOI={10.1002/adfm.201201051}, abstractNote={AbstractThe photothermal effect of metal nanoparticles embedded in polymeric materials can be used to efficiently generate local heat for in situ thermally processing within an existing material. Fluorescent probes are employed as thermal sensors to allow dynamical measurement of the amplitude and rate of temperature change within the polymer matrix. The efficacy of this technique is demonstrated in polymer nanocomposite samples with different morphological characteristics, namely nanofibrous mats and thin film samples. For similarly thick materials and both types of sample morphology, average temperature increases on the order of ≈100s °C are readily obtained with dilute nanoparticle concentrations under relatively low irradiation intensity. Thus, the in situ photothermal heating approach has great potential for controllably driving a multitude of thermal processes, such as triggering phase transitions, generating site‐specific cross‐linking, or initiating chemical reactions from within a material.}, number={24}, journal={Advanced Functional Materials}, publisher={Wiley}, author={Maity, Somsubhra and Bochinski, Jason R. and Clarke, Laura I.}, year={2012}, month={Aug}, pages={5259–5270} } @article{thoppey_bochinski_clarke_gorga_2011, title={Edge electrospinning for high throughput production of quality nanofibers}, volume={22}, ISSN={["1361-6528"]}, DOI={10.1088/0957-4484/22/34/345301}, abstractNote={A novel, simple geometry for high throughput electrospinning from a bowl edge is presented that utilizes a vessel filled with a polymer solution and a concentric cylindrical collector. Successful fiber formation is presented for two different polymer systems with differing solution viscosity and solvent volatility. The process of jet initiation, resultant fiber morphology and fiber production rate are discussed for this unconfined feed approach. Under high voltage initiation, the jets spontaneously form directly on the fluid surface and rearrange along the circumference of the bowl to provide approximately equal spacing between spinning sites. Nanofibers currently produced from bowl electrospinning are identical in quality to those fabricated by traditional needle electrospinning (TNE) with a demonstrated ∼ 40 times increase in the production rate for a single batch of solution due primarily to the presence of many simultaneous jets. In the bowl electrospinning geometry, the electric field pattern and subsequent effective feed rate are very similar to those parameters found under optimized TNE experiments. Consequently, the electrospinning process per jet is directly analogous to that in TNE and thereby results in the same quality of nanofibers.}, number={34}, journal={NANOTECHNOLOGY}, author={Thoppey, N. M. and Bochinski, J. R. and Clarke, L. I. and Gorga, R. E.}, year={2011}, month={Aug} } @article{maity_downen_bochinski_clarke_2011, title={Embedded metal nanoparticles as localized heat sources: An alternative processing approach for complex polymeric materials}, volume={52}, ISSN={["1873-2291"]}, DOI={10.1016/j.polymer.2011.01.062}, abstractNote={Metal nanoparticles were utilized as heating elements within nanofibers to demonstrate an alternative approach to thermally process nanostructured polymeric materials. In the photothermal process, resonant light excites the surface plasmon of the nanoparticle and the absorbed energy is converted into heat due to electron-phonon collisions. This heating is efficient and strongly localized, generated from the nanometer-sized metal particles embedded within the polymer. Composite polyethylene oxide (PEO) nanofibers, containing differing concentrations and types of nanoparticles, were fabricated by electrospinning and irradiated by a low intensity laser tuned specifically to the metal nanoparticle surface plasmon absorbance; aggregation of fibers, loss of fibrous structure, and ultimately, complete melting were observed. The photothermal response to irradiation increased with nanoparticle concentration as long as particle aggregation was avoided. Pure PEO nanofibers, or those containing metal nanoparticles possessing a non-resonant surface plasmon, were also irradiated but no melting occurred, demonstrating the controllable specificity of this approach.}, number={7}, journal={POLYMER}, author={Maity, Somsubhra and Downen, Lori N. and Bochinski, Jason R. and Clarke, Laura I.}, year={2011}, month={Mar}, pages={1674–1685} } @article{thoppey_bochinski_clarke_gorga_2010, title={Unconfined fluid electrospun into high quality nanofibers from a plate edge}, volume={51}, ISSN={["0032-3861"]}, DOI={10.1016/j.polymer.2010.07.046}, abstractNote={We demonstrate an easily-implemented, edge-plate geometry for electrospinning and produce high quality nanofibers from unconfined polymer fluids. We show that for electrospinning in general, the electric field gradient, not just the electric field amplitude, is a critical parameter for successful self-initiated jetting. Considering a single spinning site, the edge-plate configuration resulted in the same or a higher fabrication rate as traditional needle electrospinning, while producing nanofibers similar in quality (diameter, diameter distribution, and collected mat porosity); moreover, this novel configuration operates without the possibility of clogging and has high potential for scale-up. We analyze the fundamental physical processes which underlie edge-plate electrospinning, including electric field, working distance, and feed rate dependence and the resultant changes to the linear and whipping regions, and thus to the fiber diameter. We conclude that the edge-plate configuration functions in a remarkably similar manner to traditional needle electrospinning.}, number={21}, journal={POLYMER}, author={Thoppey, Nagarajan Muthuraman and Bochinski, Jason R. and Clarke, Laura I. and Gorga, Russell E.}, year={2010}, month={Oct}, pages={4928–4936} } @article{scott_stevens_bochinski_clarke_2008, title={Dynamics within Alkylsiloxane Self-Assembled Monolayers Studied by Sensitive Dielectric Spectroscopy}, volume={2}, ISSN={["1936-0851"]}, DOI={10.1021/nn800543j}, abstractNote={Self-assembled monolayers are a ubiquitous laboratory tool and have been the subject of many experimental investigations which have primarily focused on static properties of full coverage monolayers, with the maximum density and ordering possible. In this work, dynamics within low density, planar siloxane self-assembled monolayers are studied utilizing highly sensitive dielectric spectroscopy. Dilute, disordered films were intentionally fabricated in order to study the widest range of possible motions. At low coverage, an interacting relaxation is observed, which has similar dynamics to polyethylene-like glass transitions observed in phase-segregated side-chain polymers, despite the rigidity of the substrate and the constraint of ethyl groups in relatively short chains. As density is increased, a second local relaxation, previously observed in three-dimensional SAMs and associated with rotation within a small segment of the alkyl chain, is also observed.}, number={11}, journal={ACS NANO}, author={Scott, Mary C. and Stevens, Derrick R. and Bochinski, Jason R. and Clarke, Laura I.}, year={2008}, month={Nov}, pages={2392–2400} } @article{hudson_ticknor_sawyer_taatjes_lewandowski_bochinski_bohn_ye_2006, title={Production of cold formaldehyde molecules for study and control of chemical reaction dynamics with hydroxyl radicals}, volume={73}, DOI={10.1103/physreva.73.063404}, abstractNote={We propose a method for controlling a class of low temperature chemical reactions. Specifically, we show the hydrogen abstraction channel in the reaction of formaldehyde (H{sub 2}CO) and the hydroxyl radical (OH) can be controlled through either the molecular state or an external electric field. We also outline experiments for investigating and demonstrating control over this important reaction. To this end, we report the first Stark deceleration of H{sub 2}CO. We have decelerated a molecular beam of H{sub 2}CO essentially to rest, producing molecules at 100 mK with a density of {approx} 10{sup 6} cm{sup -3}.}, number={6}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Hudson, Eric R. and Ticknor, Christopher and Sawyer, Brian C. and Taatjes, Craig A. and Lewandowski, H. J. and Bochinski, J. R. and Bohn, J. L. and Ye, Jun}, year={2006}, month={Jun} } @article{lewandowski_hudson_bochinski_ye_2004, title={A pulsed, low-temperature beam of supersonically cooled free radical OH molecules}, volume={395}, DOI={10.1016/j.cplett.2004.07.050}, abstractNote={An improved system for creating a pulsed, low-temperature molecular beam of hydroxyl radical (OH) radicals has been developed. We use a pulsed discharge to create OH from H2O seeded in Xe during a supersonic expansion, where the high-voltage pulse duration is significantly shorter than the width of the gas pulse. The pulsed discharge allows for control of the mean speed of the molecular packet as well as maintains a low temperature supersonic expansion. A hot filament is placed in the source chamber to initiate the discharge for shorter durations and at lower voltages, resulting in a translationally and rotationally colder packet of OH molecules.}, number={1-3}, journal={Chemical Physics Letters}, publisher={Elsevier BV}, author={Lewandowski, H.J. and Hudson, Eric R. and Bochinski, J.R. and Ye, Jun}, year={2004}, month={Sep}, pages={53–57} } @article{hudson_bochinski_lewandowski_ye_2004, title={Cold free radical molecules in the laboratory frame}, DOI={10.1364/iqec.2004.imi5}, abstractNote={For scientifically interesting diatomic free radical molecules, which typically possess large electric dipole moments, Stark deceleration of weak-field seeking states is an ideal method for cold sample production. We utilize a seeded, pulsed supersonic beam in combination with an electric discharge to realize an efficient free radical source that is well-suited for use with Stark deceleration. The source apparatus creates an intense OH molecular beam whose subsequent longitudinal phase-space manipulation by precisely sequenced, pulsed inhomogeneous electric fields is directly observed by in-situ laser-induced fluorescence (LIF) detection.}, journal={Conference on Lasers and Electro-Optics/International Quantum Electronics Conference and Photonic Applications Systems Technologies}, publisher={OSA}, author={Hudson, Eric and Bochinski, J R. and Lewandowski, H J. and Ye, Jun}, year={2004} } @article{bochinski_hudson_lewandowski_ye_2004, title={Cold free-radical molecules in the laboratory frame}, volume={70}, DOI={10.1103/physreva.70.043410}, abstractNote={We report manipulation of a supersonically-cooled beam of diatomic hydroxyl radicals by precisely-sequenced inhomogeneous electric fields. In-situ observation of laser-induced fluorescence along the beam path allows for observation of longitudinal phase-space evolution.}, number={4}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Bochinski, J. R. and Hudson, Eric R. and Lewandowski, H. J. and Ye, Jun}, year={2004}, month={Oct} } @article{hudson_bochinski_lewandowski_sawyer_ye_2004, title={Efficient Stark deceleration of cold polar molecules}, volume={31}, DOI={10.1140/epjd/e2004-00138-7}, abstractNote={Stark deceleration has been utilized for slowing and trapping several species of neutral, ground-state polar molecules generated in a supersonic beam expansion. Due to the finite physical dimension of the electrode array and practical limitations of the applicable electric fields, only molecules within a specific range of velocities and positions can be efficiently slowed and trapped. These constraints result in a restricted phase space acceptance of the decelerator in directions both transverse and parallel to the molecular beam axis; hence, careful modeling is required for understanding and achieving efficient Stark decelerator operation. We present work on slowing of the hydroxyl radical (OH) elucidating the physics controlling the evolution of the molecular phase space packets both with experimental results and model calculations. From these results we deduce experimental conditions necessary for efficient operation of a Stark decelerator.}, number={2}, journal={The European Physical Journal D}, publisher={Springer Science and Business Media LLC}, author={Hudson, Eric R. and Bochinski, J. R. and Lewandowski, H. J. and Sawyer, Brian C. and Ye, Jun}, year={2004}, month={Nov}, pages={351–358} } @misc{p_j_r_h_2004, title={Method For Operating An Electrodeless Hid Lamp And An Electrodeless Lamp System}, url={https://www.lens.org/007-206-402-533-052}, number={EP 0719076 B1}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason and H, Goss Harold}, year={2004}, month={Apr} } @misc{p_j_r_h_2004, title={Verfahren Zum Betreiben Einer Elektrodenlosen Hochdruckentladungslampe Und Ein Elektrodenloses Lampensystem}, url={https://www.lens.org/192-317-024-971-329}, number={DE 69532880 D1}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason and H, Goss Harold}, year={2004}, month={May} } @article{bochinski_hudson_lewandowski_meijer_ye_2003, title={Phase Space Manipulation of Cold Free Radical OH Molecules}, volume={91}, DOI={10.1103/physrevlett.91.243001}, abstractNote={We report bunching, slowing, and acceleration of a supersonically cooled beam of diatomic hydroxyl radicals (OH). In situ observation of laser-induced fluorescence along the beam propagation path allows for detailed characterization of longitudinal phase-space manipulation of OH molecules through the Stark effect by precisely sequenced inhomogeneous electric fields.}, number={24}, journal={Physical Review Letters}, publisher={American Physical Society (APS)}, author={Bochinski, J. R. and Hudson, Eric R. and Lewandowski, H. J. and Meijer, Gerard and Ye, Jun}, year={2003} } @article{bochinski_hudson_ye_2003, title={Stark manipulation of the free radical OH}, DOI={10.1109/qels.2003.238172}, abstractNote={Our latest work towards utilizing Stark deceleration on a beam of molecular free radicals is presented. Observed signal enhancement using hexapole focusing and the necessary phase space matching conditions are discussed.}, journal={Postconference Digest Quantum Electronics and Laser Science, 2003. QELS.}, publisher={IEEE}, author={Bochinski, J.R. and Hudson, E.R. and Ye, J.}, year={2003} } @article{loftus_bochinski_mossberg, title={Magnetic trapping of ytterbium and the alkaline earths}, DOI={10.1109/qels.2001.962227}, abstractNote={Summary form only given. Atomic ytterbium (Yb), magnesium (Mg), calcium (Ca), and strontium (Sr) possess simple internal level structure and a diversity of naturally abundant fermionic and bosonic isotopes, making these atoms ideal testing grounds for cold collision theories and future studies of weakly-interacting quantum degenerate gases. Lacking useful magnetic ground-state sub-structure, however, these atoms cannot be driven into the quantum degenerate regime by pursuing the only proven strategy, ground-state magnetic trapping followed by forced RF evaporation. We propose a novel solution to this problem that involves magnetic trapping in the low-lying /sup 3/P/sub 2/ metastable excited state and demonstrate the possibility for deep magnetic traps using field gradients identical to those currently used for /sup 1/S/sub 0/-/sup 1/P/sub 1/ Yb and alkaline-earth magneto-optical traps.}, journal={Technical Digest. Summaries of papers presented at the Quantum Electronics and Laser Science Conference. Postconference Technical Digest (IEEE Cat. No.01CH37172)}, publisher={Opt. Soc. America}, author={Loftus, T. and Bochinski, J.R. and Mossberg, T.W.} } @article{loftus_bochinski_mossberg_2002, title={Magnetic trapping of ytterbium and the alkaline-earth metals}, volume={66}, DOI={10.1103/physreva.66.013411}, abstractNote={Atomic ytterbium (Yb), magnesium (Mg), calcium (Ca), and strontium (Sr) possess a simple yet versatile internal level structure and a diversity of naturally abundant fermionic and bosonic isotopes, making these systems ideal for studies of cold collisions and weakly interacting quantum degenerate gases. Unlike alkali-metal atoms, however, Yb, Mg, Ca, and Sr cannot be magnetically trapped in the ground state. We analyze a solution to this problem involving magnetic trapping in a low-lying metastable excited state and predict that significant magnetic trap populations can be obtained via continuous, in situ loading from Yb and Sr ${}^{1}{S}_{0}{\ensuremath{-}}^{1}{P}_{1}$ magneto-optical traps.}, number={1}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Loftus, T. and Bochinski, J. R. and Mossberg, T. W.}, year={2002}, month={Jul} } @article{loftus_bochinski_mossberg, title={Optical gain and loss spectra of driven degenerate two-level transitions}, DOI={10.1109/qels.2001.961802}, abstractNote={Summary form only given. Studies of the classic problem of two non-degenerate atomic energy states exposed to an intense monochromatic driving field have enabled fundamental discoveries in quantum optics including inversionless optical gain, multiphoton laser action, and electromagnetically induced transparency. Nevertheless, the level degeneracy present in many atomic systems can and has been shown to play key roles in a variety of unique driven atom dynamics ranging from light-shift mediated stimulated Raman optical gain and lasing to electromagnetically induced absorption. To date, however, the potentially rich dynamics of these novel systems has received relatively little attention. Atomic barium (Ba) possesses a diversity of naturally abundant isotopes with varying degrees of level degeneracy, making it ideally suited to studies of degenerate two-level driven atom dynamics.}, journal={Technical Digest. Summaries of papers presented at the Quantum Electronics and Laser Science Conference. Postconference Technical Digest (IEEE Cat. No.01CH37172)}, publisher={Opt. Soc. America}, author={Loftus, T. and Bochinski, J.R. and Mossberg, T.W.} } @misc{p_j_r_2001, title={Electrodeless High Intensity Discharge Lamp Energized By A Rotating Electric Field}, url={https://www.lens.org/085-701-045-655-437}, number={EP 0684629 B1}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={2001}, month={Dec} } @misc{p_j_r_2001, title={Electrodeless High Intensity Discharge Lamp Having A Boron Sulfide Fill}, url={https://www.lens.org/172-562-283-458-259}, number={EP 0788140 B1}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={2001}, month={Sep} } @misc{p_j_r_2001, title={Electrodeless High Intensity Discharge Lamp Having A Phosphorus Fill}, url={https://www.lens.org/194-362-098-982-587}, number={EP 0788141 B1}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={2001}, month={Sep} } @article{loftus_bochinski_mossberg_2001, title={Optical double-resonance cooled-atom spectroscopy}, volume={63}, DOI={10.1103/physreva.63.023402}, abstractNote={Merging laser cooling and high-resolution spectroscopy is rapidly becoming a powerful strategy for a variety of new spectroscopic experiments. The Doppler-free environment afforded by magneto-optical traps ~MOT’s! has, for example, recently enabled absorption measurements directly linking quantum interference to optical gain without population inversion in driven three-level V-scheme systems @1#. Additionally, the most accurate determination of any visible single photon atomic transition frequency @2# was recently realized using phase coherent measurements of the calcium 1 S0- 3 P1 transition in a 1 S0- 1 P1 MOT. Moreover, laser cooling has opened new avenues for hyperfine structure and linewidth measurements of one- and two-photon transitions in alkali metals @3#. V-scheme optical double-resonance spectroscopy has been used to simplify complex molecular fluorescence and absorption spectra and explore state-changing inelastic molecular collisions @4#. In the simplest rendition of this technique, selective manipulation of ground-state populations with a pump laser and observations of modulated probeinduced fluorescence allows identification of transitions that share common ground states. We present an alternative formulation of this technique that utilizes a fixed frequency cooling laser on the pump transition to selectively depopulate velocity classes in an atomic beam. This enables, through weak probe fluorescence spectra from a coupled transition, measurements of the pump transition isotope shifts and hyperfine splittings. Specifically, longitudinal laser cooling is applied to an atomic beam composed of two or more isotopes whose Doppler-broadened resonance frequencies ~Doppler profiles! overlap on the cooling transition. For a fixed laser frequency, this step generates holes in the velocity profiles of several isotopes ~the atoms are decelerated! whose spectral locations are proportional to the pump transition isotope shifts and hyperfine splittings. These holes, and thus the pump transition frequency shifts, are measured by observing probe-induced fluorescence spectra from a coupled transition on which Doppler profiles for the different isotopes are well resolved. This novel approach eliminates the need for Doppler-free measurements inherent to other experimental methods @5‐9#.}, number={2}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Loftus, T. and Bochinski, J. R. and Mossberg, T. W.}, year={2001}, month={Jan} } @article{loftus_bochinski_mossberg_2001, title={Simultaneous multi-isotope trapping of ytterbium}, volume={63}, DOI={10.1103/physreva.63.053401}, abstractNote={Working with ytterbium ~Yb!, we demonstrate dual-isotope magneto-optic traps of extreme experimental simplicity yet containing either fermion-boson or boson-boson isotope pairs. Pairs studied include Yb1Yb ~a fermion-boson mixture! and Yb1Yb and Yb1Yb ~boson-boson mixtures!. Trapping is performed using the Yb (6s)S0-(6s6p) P1 transition, an uncooled thermal source, and bichromatic trapping beams. Static and dynamic properties of the composite cloud are conveniently probed on the spinforbidden (6s)S0-(6s6p) P1 transition. A unique strategy for continuously loading these samples into magnetic traps is described.}, number={5}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Loftus, T. and Bochinski, J. R. and Mossberg, T. W.}, year={2001}, month={Apr} } @article{bochinski_yu_loftus_mossberg_2001, title={Vacuum-mediated multiphoton transitions}, volume={63}, DOI={10.1103/physreva.63.051402}, abstractNote={We have measured the emission spectra of two-level-like atoms driven by a spatially inhomogeneous bichromatic field comprised of one resonant and one off-resonant component. Under these excitation conditions, observed spectra consist of several narrow peaks appearing on top of a broad continuumlike structure. This experimental approach provides for selective observation of those spectral features having a Rabifrequency-independent emission frequency. Such emission processes involve multiphoton transitions, with one leg being spontaneous, between dressed-state levels differing only in their photonic quantum numbers; i.e., between equivalent dressed-state-doublet sublevels. Related vacuum-mediated transitions have recently been invoked as an underlying mechanism of inversionless gain.}, number={5}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Bochinski, J. R. and Yu, C. C. and Loftus, T. and Mossberg, T. W.}, year={2001}, month={Apr} } @article{bochinski_loftus_mossberg_2000, title={Laser modulation technique for single isotope spectroscopic studies}, volume={61}, DOI={10.1103/physreva.61.041404}, abstractNote={We demonstrate an atomic-beam approach to obtaining isotope specific driven-atom spectra using samples of arbitrary isotopic composition. The method employs modulation of a target isotope ground-state population by an upstream preparation laser. Desired driven-atom signals generated downstream from the preparation laser are isolated using a lock-in amplifier referenced to the preparation laser modulation frequency. In our experiments, an intensity-modulated laser resonant with the barium (6s)S0-(6s6p) P1 791.1-nm intercombination transition selectively pumps Ba atoms via radiative decays to the (6s5d)D1,2 metastable states. Dressed-atom gain studies using the (6s)S0-(6s6p) P1 553.5-nm transition demonstrate the efficacy of the method. This technique has general utility for selectively isolating specific isotopic signals in systems possessing optically controllable atomic-beam populations.}, number={4}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Bochinski, J. R. and Loftus, T. and Mossberg, T. W.}, year={2000}, month={Mar} } @article{loftus_bochinski_shivitz_mossberg_2000, title={Power-dependent loss from an ytterbium magneto-optic trap}, volume={61}, DOI={10.1103/physreva.61.051401}, abstractNote={Summary form only given. Magneto-optic trapping of Yb is facilitated by use of a strong transition of the 555.6 nm (6s/sup 2/)/sup 1/S/sub 0/-(6s6p)/sup 3/P/sub 1/ inter-combination line. This line is not radiatively closed, however, and some the decay channels terminate in metastable states, resulting in magneto-optic trapping (MOT) lifetimes that depend on the fraction of atoms in the upper level of the cooling transition. We describe a quantitative study of trap lifetime versus trapping beam power that complements earlier predictions and qualitative experimental results. Our work constitutes the first use of MOT loss rates to measure an excited-state radiative branching ratio.}, number={5}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Loftus, T. and Bochinski, J. R. and Shivitz, R. and Mossberg, T. W.}, year={2000}, month={Apr} } @article{loftus_bochinski_mossberg_2000, title={Probing magneto-optic trap dynamics through weak excitation of a coupled narrow-linewidth transition}, volume={61}, DOI={10.1103/physreva.61.061401}, abstractNote={Ytterbium ~Yb, Z570) and other alkaline-earth-like atoms possess coupled two-level-like transitions ~see Fig. 1! whose widely different natural widths @1,2# support multiple magneto-optic trapping opportunities. Specifically, the strong and nearly closed @3# S0P1 transitions are well suited, due to their large scattering rates, to cooling atomic beams @2,4– 6,9,10# and loading magneto-optic traps ~MOTs! from thermal or slowed sources @4–6,9,10#. In contrast, and due to their narrow linewidths, the spin-forbidden S0P1 transitions support MOTs with ultralow limiting temperatures and potentially high spatial densities @5,7#, and are useful for high-resolution spectroscopic studies @8–10#. Employing these two types of transitions in complementary cooling, trapping, and spectroscopic roles may ultimately provide new routes to quantum degeneracy @5,7# and high-precision optical frequency standards @1,8–10#. A staged cooling experiment using first the S0P1 and then the S0P1 transitions in strontium ~Sr! has already led to record phasespace densities in a MOT @5#. Additionally, optical spectroscopy of the S0P1 magnesium ~Mg! @9# ~calcium ~Ca! @10#! transition in S0P1 MOTs has produced fractional frequency stabilities exceeding ~approaching! that which can be obtained with atomic-beam experiments using the same species. In this Rapid Communication, we present observations, in a steady-state 398.8-nm(6s)S0-(6s6p) P1 Yb MOT, of probe fluorescence spectra induced by excitation of the Yb(6s)S0-(6s6p) P1 555.6-nm transition. We find that the Zeeman structure of the P1 excited state is completely resolved and that peak widths and splittings provide diagnostic information about the atomic cloud size, location relative to the trap magnetic field zero @11#, and potentially, the atomic velocity distribution @10#. Use of an intercombination transition to perform in situ temperature measurements may provide an alternative approach to trapdestructive time-of-flight techniques @10,12#. Since a detailed description of the apparatus has been given previously @4#, we only review the relevant features of the trapping experiment here. Approximately 10 Yb atoms, loaded with a s Zeeman slower, are held in a S0P1 Yb MOT. For the power levels used in this experiment, the trap lifetime t is limited primarily by radiative branching from the P1 state to t;400 msec @4#. Trap axial}, number={6}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Loftus, T. and Bochinski, J. R. and Mossberg, T. W.}, year={2000}, month={May} } @article{wang_greiner_bochinski_mossberg_1999, title={Experimental study of photon-echo size in optically thick media}, volume={60}, DOI={10.1103/physreva.60.r757}, abstractNote={We have studied the effect of generative-pulse amplitude, spatial profile, and temporal character as well as medium optical thickness on the power of photon and stimulated echoes. Working in atomic Yb vapor, photon echoes are observed that, absent material relaxation, are more powerful than the first generative pulse, thereby exceeding typically expected photon-echo powers by approximately two orders of magnitude. Factors crucial to the generation of powerful echoes identified through Maxwell-Bloch simulation are experimentally confirmed.}, number={2}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Wang, T. and Greiner, C. and Bochinski, J. R. and Mossberg, T. W.}, year={1999}, month={Aug}, pages={R757–R760} } @misc{p_j_r_1998, title={Electrodeless High Intensity Discharge Lamp Having A Phosphorus Fill}, url={https://www.lens.org/075-907-934-609-853}, number={US 5818167 A}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1998}, month={Oct} } @article{yu_bochinski_kordich_mossberg_ficek_1997, title={Driving the driven atom: Spectral signatures}, volume={56}, DOI={10.1103/physreva.56.r4381}, abstractNote={We have measured the emission spectrum of two-level-like Ba atoms driven by a continuous-wave bichromatic field containing a strong resonant component and a weaker component detuned from atomic resonance by the strong-field Rabi frequency. With the specified detuning, the weak field resonantly drives a transition of the atom–strong-field dressed states. Observed spectra show that each peak of the normal (single-driving-field) resonance fluorescence triplet is split into three subpeaks separated by one-half the weak-field Rabi frequency. Also seen is another triplet of peaks displaced from the atomic resonance by twice the strong-field Rabi frequency. Splitting of the normal triplet peaks can be explained through weak-field dressing of the strong-field dressed states. The origin of the additional triplet is less transparent. Comparison with theory is made.}, number={6}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Yu, C. C. and Bochinski, J. R. and Kordich, T. M. V. and Mossberg, T. W. and Ficek, Z.}, year={1997}, pages={R4381–R4384} } @misc{p_j_r_1997, title={Electrodeless High Intensity Discharge Lamp Having A Boron Sulfide Fill}, url={https://www.lens.org/137-533-462-093-900}, number={EP 0788140 A3}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1997}, month={Nov} } @misc{p_j_r_1997, title={Electrodeless High Intensity Discharge Lamp Having A Boron Sulfide Fill}, url={https://www.lens.org/108-721-940-381-795}, number={EP 0788140 A2}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1997}, month={Aug} } @misc{p_j_r_1997, title={Electrodeless High Intensity Discharge Lamp Having A Phosphorus Fill}, url={https://www.lens.org/077-398-386-713-165}, number={EP 0788141 A3}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1997}, month={Nov} } @misc{p_j_r_1997, title={Electrodeless High Intensity Discharge Lamp Having A Phosphorus Fill}, url={https://www.lens.org/036-076-949-733-073}, number={EP 0788141 A2}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1997}, month={Aug} } @article{sellin_yu_bochinski_mossberg_1997, title={Intrinsically Irreversible Multiphoton Laser Gain Mechanisms}, volume={78}, DOI={10.1103/physrevlett.78.1432}, abstractNote={Essential to the creation of laser gain is a discrimination which favors stimulated photon production over photon loss by absorption. This is typically achieved by creating a population inversion. However, irreversibility offers a natural but unrecognized mechanism for producing laser gain. We identify here a fundamental family of multiphoton laser gain processes, uniquely characterized by their composite stimulated and spontaneous nature, that provide gain independent of relative atomic state populations. This mechanism may be operating at a fundamental level in many instances of lasing without inversion. In Figs. 1(a)‐1(c), respectively, we depict exemplary one-, two-, and three-photon processes that may lead to changes in atomic and field states. We refer to the field modes involved as G, C, and S, where the C mode always represents an applied driving field. We are concerned with the conditions necessary for stimulated emission to dominate G-mode interactions.}, number={8}, journal={Physical Review Letters}, publisher={American Physical Society (APS)}, author={Sellin, P. B. and Yu, C. C. and Bochinski, J. R. and Mossberg, T. W.}, year={1997}, month={Feb}, pages={1432–1435} } @misc{p_j_r_h_1997, title={Method For Deflecting The Arc Of An Electrodeless Hid Lamp}, url={https://www.lens.org/099-108-197-104-029}, number={EP 0719076 A3}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason and H, Goss Harold}, year={1997}, month={Mar} } @misc{p_j_r_1996, title={Electrodeless High Intensity Discharge Lamp Energized By A Rotating Electric Field}, url={https://www.lens.org/002-705-717-176-285}, number={US 5498928 A}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1996}, month={Mar} } @misc{j_p_r_1996, title={Leistungskompensierte Kopplungsanordnung Für Elektrodenlose Entladungslampe}, url={https://www.lens.org/028-484-308-795-939}, number={DE 69302891 D1}, author={J, Butler Scott and P, Lapatovich Walter and R, Bochinski Jason}, year={1996}, month={Jul} } @misc{p_j_r_h_1996, title={Method For Deflecting The Arc Of An Electrodeless Hid Lamp}, url={https://www.lens.org/184-474-432-156-920}, number={US 5508592 A}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason and H, Goss Harold}, year={1996}, month={Apr} } @misc{p_j_r_h_1996, title={Method For Operating An Electrodeless Hid Lamp And An Electrodeless Lamp System}, url={https://www.lens.org/000-275-939-290-155}, number={EP 0719076 A2}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason and H, Goss Harold}, year={1996}, month={Jun} } @misc{j_p_r_1996, title={Power Balanced Coupling Structure For Electrodeless Discharge Lamp}, url={https://www.lens.org/019-178-207-347-641}, number={EP 0604935 B1}, author={J, Butler Scott and P, Lapatovich Walter and R, Bochinski Jason}, year={1996}, month={May} } @misc{p_j_r_1995, title={Electrodeless High Intensity Discharge Lamp Energized By A Rotating Electric Field.}, url={https://www.lens.org/184-429-767-923-690}, number={EP 0684629 A1}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1995}, month={Nov} } @misc{j_p_r_1994, title={Integral Impedance Matching Structure For Electrodeless Discharge Lamp}, url={https://www.lens.org/006-565-400-922-538}, number={US 5359264 A}, author={J, Butler Scott and P, Lapatovich Walter and R, Bochinski Jason}, year={1994}, month={Oct} } @misc{j_p_r_1994, title={Power Balanced Coupling Structure For Electrodeless Discharge Lamp}, url={https://www.lens.org/141-419-562-405-583}, number={US 5313144 A}, author={J, Butler Scott and P, Lapatovich Walter and R, Bochinski Jason}, year={1994}, month={May} } @misc{j_p_r_1994, title={Power Balanced Coupling Structure For Electrodeless Discharge Lamp.}, url={https://www.lens.org/073-990-151-975-942}, number={EP 0604935 A1}, author={J, Butler Scott and P, Lapatovich Walter and R, Bochinski Jason}, year={1994}, month={Jul} } @misc{p_j_r_1993, title={End Cup Applicators For High Frequency Electrodeless Lamps}, url={https://www.lens.org/069-995-495-580-977}, number={US 5241246 A}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1993}, month={Aug} } @misc{p_j_r_1992, title={Loop Applicator For High Frequency Electrodeless Lamps}, url={https://www.lens.org/123-011-560-951-466}, number={US 5130612 A}, author={P, Lapatovich Walter and J, Butler Scott and R, Bochinski Jason}, year={1992}, month={Jul} }