Now showing items 1-10 of 505
AlGaN quadruple-band photodetectors
Quadruple back-illuminated ultraviolet metal-semiconductor-metal photodetectors with four different spectral responsivity bands were demonstrated. The average of the full-width at half-maximum (FWHM) of the quantum efficiency ...
Photonic-crystal-based resonant-cavity-enhanced detectors
A layer-by-layer three-dimensional photonic crystal, with a full photonic bandgap (PBG) in all directions is proposed. The electrical fields in the cavities of this crystal are usually enhanced, and by placing active devices ...
Ferroelectric based tuneable SRR based metamaterial for microwave applications
We discuss the possibility of achieving tunable split ring resonators at microwave frequencies. One method is to use varying capacitance values to tune the magnetic resonance frequency. As another method ferroelectric thin ...
Resonant cavity-enhanced detectors embedded in photonic crystals
Summary form only given. We demonstrate the resonant-cavity-enhanced effect by placing microwave detectors in a layer-by-layer photonic crystal. We used the output of a network analyzer as the microwave source, and fed the ...
InGaN/GaN based LEDs with electroluminescence in violet, blue, and green tuned by epitaxial growth temperature
In this work, we present a full set of InGaN LEDs based on a single optimal InGaN/GaN quantum design with emission wavelengths spanning from green to blue to violet by tuning the active layer growth temperature to precisely ...
Experimental observation of true left-handed metamaterial
We report a true left-handed (LH) behavior in composite metamaterials. The magnetic resonance of the SRR structure is demonstrated. Plasma frequency of the LH material is shown to be lower than that of the wires.
Structural field plate length optimization for high power applications
In this work, we report GaN high-electron-mobility-transistors (HEMTs) on SiC with field plates of various dimensions for optimum performance. 0.6 μm gate length, 3 μm drain source space AlGaN/GaN HEMTs with field-plate ...
SbSI based photonic crystal superlattices: band structure and optics
In this work, we present an investigation of the optical properties and band structure calculations for the photonic crystal structures (PCs) based on one-dimensional (1D)-photonic crystal. Here we use 1D SbSI based layers ...
Negative refraction and focusing of electromagnetic waves by photonic crystals
In this work, we study the negative refraction and focusing effect by a metallodielectric photonic crystal. We show that by using a metallodielectric photonic crystal it is possible to obtain negative refraction for large ...
Two-dimensional left-handed metamaterial with a negative refractive index
We present a two-dimensional metamaterial with left-handed properties in a certain frequency range where both effective dielectric permittivity and magnetic permeability is simultaneously negative. A wedge-shaped metamaterial ...