Publications

Found 23 results
Author Title Type [ Year(Asc)]
Filters: Author is Speck, J. S.  [Clear All Filters]
2025
Wang, M., W. Gong, F. Wu, S. P. DenBaars, S. Nakamura, and J. S. Speck, "10.4% external quantum efficiency 294 nm UV LEDs at 20 A/cm^2 with a fully transparent tunnel junction", Optics Express, vol. 33, pp. 19876–19884, 2025.
Wang, M., S. Mu, J. S. Speck, and C. G. Van de Walle, "First-Principles Study of Twin Boundaries and Stacking Faults in β-Ga2O3", Advanced Materials Interfaces, vol. 12, pp. 2300318, 2025.
Rebollo, S., Y. Liu, C. Peterson, S. Krishnamoorthy, and J. S. Speck, "Growth of nitrogen-doped (010) β-Ga2O3 by plasma-assisted molecular beam epitaxy using an O2/N2 gas mixture", Applied Physics Letters, vol. 126, 2025.
Wissel-Garcia, A. E., F. Wu, and J. S. Speck, "Growth regimes of (0001) AlN by ammonia molecular beam epitaxy", Journal of Vacuum Science & Technology A, vol. 43, 2025.
Yapparov, R., A. Quevedo, T. Tak, S. Nakamura, S. P. DenBaars, J. S. Speck, and others, "Impact of threading dislocations on the V-defect assisted lateral carrier injection and recombination in InGaN quantum well LEDs", Applied Physics Letters, vol. 126, 2025.
Wang, M., W. Gong, F. Wu, T. Tak, S. P. DenBaars, S. Nakamura, and J. S. Speck, "Increasing light extraction efficiency for UV LEDs with a low coverage p-GaN hole injection layer", Optics Express, vol. 33, pp. 19391–19398, 2025.
Huang, H. C., S. M. Chen, C. Weisbuch, J. S. Speck, and Y. R. Wu, "The influence of V-defects, leakage, and random alloy fluctuations on the carrier transport in red InGaN MQW LEDs", Applied Physics Reviews, vol. 12, 2025.
Krishnamoorthy, S., Y. Liu, S. Roy, and J. S. Speck, "(Invited) Novel Superheterojunctions for Ultra-Low Resistance Ga2O3 and GaN Power Switches", ECS Meeting Abstracts, vol. 248, pp. 1715, 2025.
Roy, S., C. N. Saha, C. Peterson, W. J. Mitchell, J. S. Speck, and S. Krishnamoorthy, "Multi-fin β-Ga2O3 Vertical FinFET with Interfin Field Oxide Exhibiting a Breakdown Voltage of 1.8 kV and Power Figure of Merit of 1 GW/cm^2", IEEE Electron Device Letters, vol. 47, pp. 341–344, 2025.
Yapparov, R., M. S. Wong, T. Tak, S. P. DenBaars, J. S. Speck, and S. Marcinkevičius, "Origin of reduced efficiency in GaN-based micro-LEDs studied by scanning near-field optical microscopy", Applied Physics Letters, vol. 126, 2025.
Biegler, Z. J., A. A. Allerman, and J. S. Speck, "Removal of Si impurities from GaN regrowth interfaces using XeF$_2$", Applied Physics Letters, vol. 127, 2025.
Tak, T., W. Y. Ho, I. Celupica-Liu, Y. C. Chow, J. Peretti, C. Weisbuch, and J. S. Speck, "Trap-assisted Auger–Meitner recombination in GaN p-i-n diodes", Physical Review B, vol. 111, pp. 155308, 2025.
Tak, T., Y. C. Chow, S. Nakamura, S. P. DenBaars, C. Weisbuch, and J. S. Speck, "Unexpected origin of the quantum efficiency reduction in long-wavelength (In,Ga)N light-emitting diodes", Physical Review Applied, vol. 23, pp. 034002, 2025.
2023
Chow, Y. C., C. Lynsky, S. Nakamura, S. P. DenBaars, C. Weisbuch, and J. S. Speck, "Low-efficiency-droop c-plane InGaN/GaN light-emitting diodes through the use of thick single quantum wells and doped barriers", Journal of Applied Physics, vol. 133, 04, 2023.
Cadena, R. M., D. R. Ball, E. X. Zhang, S. Islam, A. Senarath, M. W. McCurdy, E. Farzana, J. S. Speck, N. Karom, A. O’Hara, et al., "Low-Energy Ion-Induced Single-Event Burnout in Gallium Oxide Schottky Diodes", IEEE Transactions on Nuclear Science, vol. 70, pp. 363-369, 2023.
2022
Chow, Y. C., C. Lynsky, S. Nakamura, S. P. DenBaars, C. Weisbuch, and J. S. Speck, "Impact of doped barriers on the recombination coefficients of c-plane InGaN/GaN single quantum well light-emitting diodes", Applied Physics Letters, vol. 121, 11, 2022.
Qwah, K. S., M. Monavarian, W. Y. Ho, Y.-R. Wu, and J. S. Speck, "Vertical hole transport through unipolar InGaN quantum wells and double heterostructures", Phys. Rev. Mater., vol. 6, pp. 044602, Apr, 2022.
2021
Chow, Y. C., C. Lynsky, F. Wu, S. Nakamura, S. P. DenBaars, C. Weisbuch, and J. S. Speck, "Reduction of efficiency droop in c-plane InGaN/GaN light-emitting diodes using a thick single quantum well with doped barriers", Applied Physics Letters, vol. 119, 11, 2021.
2019
Smirnov, A. M., E. C. Young, V. E. Bougrov, J. S. Speck, and A. E. Romanov, "Stress relaxation in semipolar and nonpolar III-nitride heterostructures by formation of misfit dislocations of various origin", Journal of Applied Physics, vol. 126, pp. 245104, 2019.
2018
Reparaz, J. S., P. K. da Silva, A. H. Romero, J. Serrano, M. R. Wagner, G. Callsen, S. J. Choi, J. S. Speck, and A. R. Goñi, "Comparative study of the pressure dependence of optical-phonon transverse-effective charges and linewidths in wurtzite InN", Phys. Rev. B, vol. 98, pp. 165204, Oct, 2018.
Hahn, W., J.-M. Lentali, P. Polovodov, N. Young, S. Nakamura, J. S. Speck, C. Weisbuch, M. Filoche, Y.-R. Wu, M. Piccardo, et al., "Evidence of nanoscale Anderson localization induced by intrinsic compositional disorder in InGaN/GaN quantum wells by scanning tunneling luminescence spectroscopy", Phys. Rev. B, vol. 98, pp. 045305, Jul, 2018.
2010
Tyagi, A., R. M. Farrell, K. M. Kelchner, C.-Y. Huang, P. S. Hsu, D. A. Haeger, M. T. Hardy, C. Holder, K. Fujito, D. A. Cohen, et al., "AlGaN-Cladding Free Green Semipolar GaN Based Laser Diode with a Lasing Wavelength of 506.4 nm", Applied Physics Express, vol. 3, pp. 011002, 2010.
2007
Tyagi, A., H. Zhong, N. N. Fellows, M. Iza, J. S. Speck, S. P. DenBaars, and S. Nakamura, "High Brightness Violet InGaN/GaN Light Emitting Diodes on Semipolar (101̄1̄) Bulk GaN Substrates", Japanese Journal of Applied Physics, vol. 46, pp. L129-L131, 2007.