Guoyi Zhang

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We present a grating model of two-dimensional (2D) rigorous coupled wave analysis (RCWA) to study top diffraction gratings on light-emitting diodes (LEDs). We compare the integrated-transmission of the non-grating, rectangular-grating, and triangular-grating cases for the same grating period of 6 µm, and show that the triangular grating has the best(More)
Human potassium channels are widely inhibited by peptide toxins from venomous animals. However, no human endogenous peptide inhibitor has been discovered so far. In this study, we demonstrate for the first time using electrophysiological techniques, that endogenous human β–defensin 2 (hBD2) is able to selectively and dose-dependently inhibit the human(More)
We present simulation results of the indium tin oxide (ITO) top diffraction grating using a rigorous couple wave analysis (RCWA) for GaN LEDs. We study three different nano-structure patterns: cylindrical pillar grating, conical pillar grating, and cylindrical nano-hole grating. We show the light transmission improvement with nano-grating designs and(More)
A 3-fold symmetric photonic-crystal grating is simulated using improved FDTD-model. Transmission gratings are optimized. Then, the best cases are simulated in GaN-LED models. The maximum extraction efficiency improvement is 40x greater compared to conventional LEDs. 1. Introduction Light emitting diodes (LED) have found many applications such as residential(More)
An anodic aluminum oxide (AAO) patterned sapphire substrate, with the lattice constant of 520 ± 40 nm, pore dimension of 375 ± 50 nm, and height of 450 ± 25 nm was firstly used as a nanoimprint lithography (NIL) stamp and imprinted onto the surface of the green light-emitting diode (LED). A significant light extraction efficiency (LEE) was improved by 116%(More)
InGaN/GaN nanorod light-emitting diode (LED) arrays were fabricated using nanoimprint and reactive ion etching. The diameters of the nanorods range from 120 to 300 nm. The integral photoluminescence (PL) intensity for 120 nm nanorod LED array is enhanced as 13 times compared to that of the planar one. In angular-resolved PL (ARPL) measurements, there are(More)