Due to the wide band gap energy and high breakdown electric field of GaN, heterostructure transistors made from it are promising candidates for high power and high frequency applications. However, one issue that prevents the wide deployment of GaN HEMTs is their reliability. Research has been actively trying to improve the reliability of these devices. In spite of this, detailed understanding o...

Taking advantage of strong 4-photon absorption of l e v light in GaN samples, we demonstrated the fmt ever 4-photon microscopy using GaN material system. Combining with 3-photon fluorescence and second and third harmonic generation microscopies, we studied a lateral overgrown GaN sample with high 3D resolution. Complete information regarding the distribution of growth quality, defect state, and...

In this paper, GaN-based light-emitting diodes (LEDs) with photonic quasi-crystal (PQC) structure on p-GaN surface and n-side roughing by nano-imprint lithography are fabricated and investigated. At an injection current of 20 mA, the LED with PQC structure on p-GaN surface and n-side roughing increased the light output power of the InGaN/GaN multiple quantum well LEDs by a factor of 1.42, and t...

Comprehensive physics-based simulations of GaN-based light-emitting diodes and laser diodes are presented. The talk discusses unique material properties of nitride compounds as well as performance-limiting physical mechanisms like self-heating, current crowding, and carrier leakage. Measurements are used to validate the models and to extract critical device parameters.

O and Si donors in GaN are studied by Raman spectroscopy under hydrostatic pressure p. The ground state of O is found to transfer from a shallow level to a deep gap state at p . 20 GPa reminiscent of DX centers in GaAs. Transferred to AlxGa12xN we predict that O induces a deep gap state for x . 0.40. In GaN:Si no such state is induced up to the highest pressure obtained sp ­ 25 GPad equivalent ...

The fabrication procedure of transparent n+-ZnO–p-GaN ohmic junctions has been described. The influence of consecutive technological steps on the electrical, structural and electronic properties of the junction has been studied. The results indicate that the predeposition of Au nucleation film plays a crucial role for the final contact properties. The ohmic behaviour is explained in terms of fo...

We apply an extension of generative adversarial networks (GANs) [8] to a conditional setting. In the GAN framework, a “generator” network is tasked with fooling a “discriminator” network into believing that its own samples are real data. We add the capability for each network to condition on some arbitrary external data which describes the image being generated or discriminated. By varying the ...

Ara A. Asatryan,1 Lindsay C. Botten,1 Michael A. Byrne,1 Valentin D. Freilikher,2 Sergey A. Gredeskul,3,4 Ilya V. Shadrivov,4 Ross C. McPhedran,5 and Yuri S. Kivshar4,6 1Department of Mathematical Sciences, Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), University of Technology, Sydney, New South Wales 2007, Australia 2Department of Physics, Bar-Ilan University, Raman-Gan 5...

Kanglin Liu Abstract Generative Adversarial Networks (GANs) are powerful generative models, but suffer from training instability. The recent proposed Wasserstein GAN with gradient penalty (WGAN-GP) makes progress toward stable training. Gradient penalty acts as the role of enforcing a Lipschitz constraint. Further investigation on gradient penalty shows that gradient penalty may impose restrict...

The price system, the adjustment of prices to changes in market conditions, is the primary mechanism by which markets function and by which the three most basic questions get answered: what to produce, how much to produce and for whom to produce. To the behaviour of price and price system, therefore, have fundamental implications for many key issues in microeconomics and industrial organization...