@article{dhawan_du_batchelor_wang_leonard_misra_ozturk_gerhold_vo-dinh_2011, title={Hybrid Top-Down and Bottom-Up Fabrication Approach for Wafer-Scale Plasmonic Nanoplatforms}, volume={7}, ISSN={["1613-6810"]}, DOI={10.1002/smll.201002186}, abstractNote={Bridging the nanoscale level of probe fabrication and the megascale dimensions of sensor systems is one of the greatest challenges in the development of large-area plasmonic sensing platforms. We report a generalized hybrid nanofabrication approach combining top-down (deep-UV lithography) and bottom-up (controlled lateral epitaxial growth and atomic layer deposition) fabrication techniques for the development of nanostructured platforms. This technology allows the development of reproducible substrates with controlled sub-10 nm gaps between plasmonic nanostructures over an entire 6 inch wafer (1 inch ≈ 2.54 cm). By integrating soft matter (DNA probes) and hard matter (silicon nanochips), these}, number={6}, journal={SMALL}, author={Dhawan, Anuj and Du, Yan and Batchelor, Dale and Wang, Hsin-Neng and Leonard, Donovon and Misra, Veena and Ozturk, Mehmet and Gerhold, Michael D. and Vo-Dinh, Tuan}, year={2011}, month={Mar}, pages={727–731} }
 @article{vo-dinh_dhawan_norton_khoury_wang_misra_gerhold_2010, title={Plasmonic Nanoparticles and Nanowires: Design, Fabrication and Application in Sensing}, volume={114}, ISSN={["1932-7455"]}, DOI={10.1021/jp911355q}, abstractNote={This study involves two aspects of our investigations of plasmonics-active systems: (i) theoretical and simulation studies and (ii) experimental fabrication of plasmonics-active nanostructures. Two types of nanostructures are selected as the model systems for their unique plasmonics properties: (1) nanoparticles and (2) nanowires on substrate. Special focus is devoted to regions where the electromagnetic field is strongly concentrated by the metallic nanostructures or between nanostructures. The theoretical investigations deal with dimers of nanoparticles and nanoshells using a semi-analytical method based on a multipole expansion (ME) and the finite-element method (FEM) in order to determine the electromagnetic enhancement, especially at the interface areas of two adjacent nanoparticles. The experimental study involves the design of plasmonics-active nanowire arrays on substrates that can provide efficient electromagnetic enhancement in regions around and between the nanostructures. Fabrication of these nanowire structures over large chip-scale areas (from a few millimeters to a few centimeters) as well as FDTD simulations to estimate the EM fields between the nanowires are described. The application of these nanowire chips using surface-enhanced Raman scattering (SERS) for detection of chemicals and labeled DNA molecules is described to illustrate the potential of the plasmonics chips for sensing.}, number={16}, journal={JOURNAL OF PHYSICAL CHEMISTRY C}, author={Vo-Dinh, Tuan and Dhawan, Anuj and Norton, Stephen J. and Khoury, Christopher G. and Wang, Hsin-Neng and Misra, Veena and Gerhold, Michael D.}, year={2010}, month={Apr}, pages={7480–7488} }
 @article{dhawan_muth_leonard_gerhold_gleeson_vo-dinh_russell_2008, title={Focused in beam fabrication of metallic nanostructures on end faces of optical fibers for chemical sensing applications}, volume={26}, ISSN={["1071-1023"]}, DOI={10.1116/1.3013329}, abstractNote={Focused ion beam (FIB) fabrication of fiber optic sensors, mainly chemical sensors, which are based on plasmonics-active nanostructures formed on the cleaved tips of optical fibers, is reported. The nanostructures fabricated included nanoholes in optically thick metallic films as well as metallic nanopillars and nanorods. The sensing mechanism is based on detecting shifts in surface plasmon resonances (SPRs) associated with nanoholes in metallic films and localized SPRs of metallic nanopillars and nanorods, when the refractive index of the medium surrounding the nanostructures is changed. These sensors can be employed for the detection of chemical agents in air as well as liquid media surrounding the sensors. FIB milling was employed to fabricate ordered arrays of nanoholes in optically thick (100–240nm) metallic films deposited on cleaved end faces of multimode, four-mode, and single-mode optical fibers. Separately, metallic nanorods and nanopillars were formed by first depositing a metallic (gold or silver) film on tips of optical fibers, which was followed by FIB milling large area patterns to form freestanding nanorods and nanopillars. Utilizing FIB allows engineering nanostructure geometries, i.e., nanostructure shapes and sizes that are chosen based on the plasmon resonances associated with them. Formation of periodic arrays of nanoholes provides a means of tuning plasmon resonance peaks, associated with extraordinary transmission of light through the array of nanoholes in the metallic films, based on periodicity and shape of the nanoholes as well as on refractive index changes to form sensitive chemical sensors.}, number={6}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B}, author={Dhawan, A. and Muth, J. F. and Leonard, D. N. and Gerhold, M. D. and Gleeson, J. and Vo-Dinh, T. and Russell, P. E.}, year={2008}, month={Nov}, pages={2168–2173} }
 @article{xu_liu_cui_gerhold_wang_nagel_lippert_2007, title={Laser-assisted forward transfer of multi-spectral nanocrystal quantum dot emitters}, volume={18}, number={2}, journal={Nanotechnology}, author={Xu, J. and Liu, J. and Cui, D. H. and Gerhold, M. and Wang, A. Y. and Nagel, M. and Lippert, T. K.}, year={2007} }
 @article{voitenko_muth_gerhold_cui_xu_2007, title={Tunable photoluminescence of polymer doped with PbSe quantum dots}, volume={27}, ISSN={["0928-4931"]}, DOI={10.1016/j.msec.2006.09.018}, abstractNote={Semiconductor nanoparticle/polymer composites potentially allow the design of photonic materials for optoelectronic devices. The optical characteristics of PbSe quantum dots placed in polymer matrices are investigated for potential applications in electrically controlled absorption modulators and integrated optical circuit components. The photoluminescence yield, shape of absorption band, and effects of size variation of PbSe quantum dots on spectral features are analyzed near the absorption edge of host polymers for the different concentrations of nanocrystals in the composite. It was found that for quantum dots of nominally the same size, there is a strong dependence of position of the absorption peaks in the spectrum depending on the concentration of quantum dots. This results in the emission in the 1500–1600 nm range being tunable with quantum dot concentration. A second emission in the 1200–1300 nm range was also observed and energy transfer from the polymer matrix to the quantum dot appears to mediate the strength of this photoluminescence.}, number={5-8}, journal={MATERIALS SCIENCE & ENGINEERING C-BIOMIMETIC AND SUPRAMOLECULAR SYSTEMS}, author={Voitenko, Igor and Muth, J. F. and Gerhold, Michael and Cui, Dehu and Xu, Jian}, year={2007}, month={Sep}, pages={1078–1081} }
 @article{cui_xu_zhu_paradee_ashok_gerhold_2006, title={Harvest of near infrared light in PbSe nanocrystal-polymer hybrid photovoltaic cells}, volume={88}, number={18}, journal={Applied Physics Letters}, author={Cui, D. H. and Xu, J. and Zhu, T. and Paradee, G. and Ashok, S. and Gerhold, M.}, year={2006} }
 @article{cui_xu_xu_paradee_lewis_gerhold_2006, title={Infrared photodiode based on colloidal PbSe nanocrystal quantum dots}, volume={5}, ISSN={["1941-0085"]}, DOI={10.1109/TNANO.2006.877432}, abstractNote={We report in this paper our studies on the photoconductivity and photovoltaic effects of colloidal PbSe nanocrystal quantum dots (NQDs) which were embedded in conductive polymer matrices to form hybrid polymer/NQD infrared photodiodes. The generation of photocarriers in PbSe NQDs and their transport in NQD-polymer composites were described by a simplified band diagram picture of the device. Both photocurrent and photovoltage outputs were measured from the NQD-incorporated photodiode upon the illumination of near-infrared (NIR) light, whereas the net polymer-based devices do not exhibit any photoresponsivity. The intensity dependence of the photocurrent indicates the pseudomonomolecular recombination kinetics in the NQD-polymer composite. The measured photocurrent spectrum is consistent with the absorption characteristic of PbSe NQDs. Further enhancement of the photodiode efficiency can be achieved by engineering the nanocrystal surface to reduce the potential barriers due to the ligant capping molecules}, number={4}, journal={IEEE TRANSACTIONS ON NANOTECHNOLOGY}, author={Cui, Dehu and Xu, Jian and Xu, Sheng-Yong and Paradee, Gary and Lewis, Bradley A. and Gerhold, Michael D.}, year={2006}, month={Jul}, pages={362–367} }
 @article{xu_cui_lewis_wang_xu_gerhold_2005, title={Microcavity light-emitting devices based on colloidal semiconductor nanocrystal quantum dots}, volume={17}, ISSN={["1941-0174"]}, DOI={10.1109/LPT.2005.856398}, abstractNote={This letter describes the design, fabrication, and characterization of a microcavity-electroluminescence (EL) device based on colloidal semiconductor nanocrystal quantum dots (NQDs). The device was fabricated by sandwiching a solution-cast film of light-emitting CdSe-CdS core-shell NQDs between two metal mirrors to form a resonant microcavity structure. We have observed a significant reduction in EL emission bandwidth from the fabricated device. Further improvement of the emission efficiency of the NQD-microcavity-EL devices can be achieved upon the minimization of the losses that are pertinent to metal mirrors.}, number={10}, journal={IEEE PHOTONICS TECHNOLOGY LETTERS}, author={Xu, J and Cui, DH and Lewis, BA and Wang, AY and Xu, SY and Gerhold, M}, year={2005}, month={Oct}, pages={2008–2010} }
 @inproceedings{hoffmann_gerhold_kirste_rice_akouala_xie_mita_collazo_sitar, title={Fabrication and characterization of lateral polar GaN structures for second harmonic generation}, volume={8631}, booktitle={Quantum sensing and nanophotonic devices x}, author={Hoffmann, M. P. and Gerhold, M. and Kirste, R. and Rice, A. and Akouala, C. R. and Xie, J. Q. Q. and Mita, S. and Collazo, R. and Sitar, Z.} }