Promising material properties of GaN, e.g., wide bandgap, high saturation velocity, and high thermal stability, make it an excellent material for high-power, high-frequency, and high-temperature applications. For some specific applications which require the device to operate at elevated temperatures, modeling and simulation provide very meaningful insights about the thermal device behavior. In ...

The band discontinuities between GaN and InN, as well as InGaN alloys, are key parameters for the design of nitride-based light emitters. Values reported to date are subject to large uncertainties due to strain effects at this highly mismatched interface. We have investigated the band lineups using first-principles calculations with explicit inclusion of strains and atomic relaxations at the in...

Generative adversarial networks (GANs) are successful deep generative models. They are based on a two-player minimax game. However, the objective function derived in the original motivation is changed to obtain stronger gradients when learning the generator. We propose a novel algorithm that repeats density ratio estimation and f-divergence minimization. Our algorithm offers a new unified persp...

We have studied experimentally the effect of ambient temperature on performance of the surface-passivated Al0.2Ga0.8N/GaN heterostructure field-effect transistors in the temperature range from 25°C to 250°C. The measured data have been compared with physics-based modeling of the GaN transistor characteristics under different ambient temperatures. The experimental data, showing about 33% degrada...

The mechanisms by which axonal degeneration occurs, even in the presence of apparently normal myelin sheaths, remain unknown. In this issue, Yin et al. (2016. J. Cell Biol. https://doi.org/10.1083/jcb.201607099) study mutant mice in which proteolipid protein is replaced by the peripheral myelin protein P0 and describe a number of early axonal abnormalities, which together suggest that aberrant ...

Oleg G. Shpyrko,1,2,* Reinhard Streitel,1 Venkatachalapathy S. K. Balagurusamy,1 Alexei Yu. Grigoriev,1 Moshe Deutsch,3 Benjamin M. Ocko,4 Mati Meron,5 Binhua Lin,5 and Peter S. Pershan1 1Department of Physics and School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA 2Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 604...

We present ab-initio local density FLAPW calculations on non–reactive N– terminated [001] ordered GaN/Ag and GaN/Au interfaces and compare the results (such as metal induced gap states and Schottky barrier heights) with those obtained for GaN/Al, in order to understand the dependence of the relevant electronic properties on the deposited metal. Our results show that the density of gap states is...

In this work we evaluate the influence of the Al2O3 ALD deposition technique on AlGaN/GaN MIS-HEMT structures. It has been found that using O2 plasma as oxidizer instead of water could increase the threshold voltage considerably while greatly reducing gate leakage current. C(V) measurements have shown a very fast on/off transition even at 1kHz, with low frequency dispersion, while a record slop...

A novel, miniaturized optoelectronic tweezers (OET) system has been developed using a CMOS-controlled GaN micro-pixelated light emitting diode (LED) array as an integrated micro-light source. The micro-LED array offers spatio-temporal and intensity control of the emission pattern, enabling the creation of reconfigurable virtual electrodes to achieve OET. In order to analyse the mechanism respon...

The Fermi level position in (Ga,Mn)N has been determined from the period-analysis of GaN-related Franz-Keldysh oscillation obtained by contactless electroreflectance in a series of carefully prepared by molecular beam epitaxy GaN/Ga1-xMnxN/GaN(template) bilayers of various Mn concentration x. It is shown that the Fermi level in (Ga,Mn)N is strongly pinned in the middle of the band gap and the t...