@article{sengupta_dangi_krylyuk_davydov_pavlidis_2022, title={Phase transition of Al2O3-encapsulated MoTe2 via rapid thermal annealing}, volume={121}, ISSN={["1077-3118"]}, DOI={10.1063/5.0097844}, abstractNote={Among group VI transition metal dichalcogenides, MoTe2 is predicted to have the smallest energy offset between semiconducting 2H and semimetallic 1T′ states. This makes it an attractive phase change material for both electronic and optoelectronic applications. Here, we report fast, nondestructive, and full phase change in Al2O3-encapsulated 2H-MoTe2 thin films to 1T′-MoTe2 using rapid thermal annealing at 900 °C. Phase change was confirmed using Raman spectroscopy after a short annealing duration of 10 s in both vacuum and nitrogen ambient. No thickness dependence of the transition temperatures was observed for flake thickness ranging from 1.5 to 8 nm. These results represent a major step forward in understanding the structural phase transition properties of MoTe2 thin films using external heating and underline the importance of surface encapsulation for avoiding thin film degradation.}, number={3}, journal={APPLIED PHYSICS LETTERS}, author={Sengupta, Rohan and Dangi, Saroj and Krylyuk, Sergiy and Davydov, Albert V. and Pavlidis, Spyridon}, year={2022}, month={Jul} }
 @article{khachariya_mita_reddy_dangi_dycus_bagheri_breckenridge_sengupta_rathkanthiwar_kirste_et al._2022, title={Record >10 MV/cm mesa breakdown fields in Al0.85Ga0.15N/Al0.6Ga0.4N high electron mobility transistors on native AlN substrates}, volume={120}, ISSN={["1077-3118"]}, DOI={10.1063/5.0083966}, abstractNote={The ultra-wide bandgap of Al-rich AlGaN is expected to support a significantly larger breakdown field compared to GaN, but the reported performance thus far has been limited by the use of foreign substrates. In this Letter, the material and electrical properties of Al0.85Ga0.15N/Al0.6Ga0.4N high electron mobility transistors (HEMT) grown on a 2-in. single crystal AlN substrate are investigated, and it is demonstrated that native AlN substrates unlock the potential for Al-rich AlGaN to sustain large fields in such devices. We further study how Ohmic contacts made directly to a Si-doped channel layer reduce the knee voltage and increase the output current density. High-quality AlGaN growth is confirmed via scanning transmission electron microscopy, which also reveals the absence of metal penetration at the Ohmic contact interface and is in contrast to established GaN HEMT technology. Two-terminal mesa breakdown characteristics with 1.3 μm separation possess a record-high breakdown field strength of ∼11.5 MV/cm for an undoped Al0.6Ga0.4N-channel layer. The breakdown voltages for three-terminal devices measured with gate-drain distances of 4 and 9 μm are 850 and 1500 V, respectively.}, number={17}, journal={APPLIED PHYSICS LETTERS}, author={Khachariya, Dolar and Mita, Seiji and Reddy, Pramod and Dangi, Saroj and Dycus, J. Houston and Bagheri, Pegah and Breckenridge, M. Hayden and Sengupta, Rohan and Rathkanthiwar, Shashwat and Kirste, Ronny and et al.}, year={2022}, month={Apr} }
 @article{liu_movahed_dangi_pan_kaur_bilinovich_faison_leighton_wang_williams_et al._2020, title={DNA looping by two 5-methylcytosine-binding proteins quantified using nanofluidic devices}, volume={13}, ISSN={["1756-8935"]}, DOI={10.1186/s13072-020-00339-7}, abstractNote={Abstract Background MeCP2 and MBD2 are members of a family of proteins that possess a domain that selectively binds 5-methylcytosine in a CpG context. Members of the family interact with other proteins to modulate DNA packing. Stretching of DNA–protein complexes in nanofluidic channels with a cross-section of a few persistence lengths allows us to probe the degree of compaction by proteins. Results We demonstrate DNA compaction by MeCP2 while MBD2 does not affect DNA configuration. By using atomic force microscopy (AFM), we determined that the mechanism for compaction by MeCP2 is the formation of bridges between distant DNA stretches and the formation of loops. Conclusions Despite sharing a similar specific DNA-binding domain, the impact of full-length 5-methylcytosine-binding proteins can vary drastically between strong compaction of DNA and no discernable large-scale impact of protein binding. We demonstrate that ATTO 565-labeled MBD2 is a good candidate as a staining agent for epigenetic mapping.}, number={1}, journal={EPIGENETICS & CHROMATIN}, author={Liu, Ming and Movahed, Saeid and Dangi, Saroj and Pan, Hai and Kaur, Parminder and Bilinovich, Stephanie M. and Faison, Edgar M. and Leighton, Gage O. and Wang, Hong and Williams, David C., Jr. and et al.}, year={2020}, month={Mar} }
 @article{dangi_riehn_2019, title={Nanoplumbing with 2D Metamaterials}, volume={15}, ISSN={["1613-6829"]}, url={https://doi.org/10.1002/smll.201803478}, DOI={10.1002/smll.201803478}, abstractNote={Complex manipulations of DNA in a nanofluidic device require channels with branches and junctions. However, the dynamic response of DNA in such nanofluidic networks is relatively unexplored. Here, the transport of DNA in a 2D metamaterial made by arrays of nanochannel junctions is investigated. The mechanism of transport is explained as Brownian motion through an energy landscape formed by the combination of the confinement free energy of DNA and the effective potential of hydrodynamic flow, which both can be tuned independently within the device. For the quantitative understanding of DNA transport, a dynamic mean-field model of DNA at a nanochannel junction is proposed. It is shown that the dynamics of DNA in a nanofluidic device with branched channels and junctions is well described by the model.}, number={2}, journal={SMALL}, publisher={Wiley}, author={Dangi, Saroj and Riehn, Robert}, year={2019}, month={Jan} }