The electrical properties of GaN pin diodes with a 3 um i-layer grown on different kinds of hemisphere-patterned sapphire substrates (PSS) are measured by current-voltage, capacitance-voltage and deep-level transient spectroscopy (DLTS).

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Finite-Difference Time-Domain (FDTD) method and Hybridization model are used to analyze both the transverse and longitudinal model of Au rod–in-shell nano structures. Higher order anti-bonding Longitudinal LSPR modes were observed. Our findings could provide a new perspective on the design of nanostructures for bio-medical applications.

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The transmission spectrum of PEC nano-hole array can be mapped to that of silver nano-hole array through dispersion relation of the fundamental waveguide modes of PEC (TE11) and metal (HE11).

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The scattering properties of nano-structure particles are studied using an in-house developed finite-difference time-domain (FDTD) method numerical simulator. Electromagnetic responses of metal-insulator-metal (MIM) nanodisks are calculated and the resonant bonding and anti-bonding modes due to the coupling between two metal regions are investigated.

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An efficient way for nanostructure fabrication based on femtosecond laser induced forward transfer technique is well demonstrated. The optical property of fabricated multilayer SRR array investigated by optical measurements agrees well with finite-difference time-domain simulations. It markedly extends the laser direct writing technique to a wide application in metamaterials fabrication.

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Antibonding-plasmonic-dipolar modes of gold nanoantennas (NAs) are excited by evanescent waves. Comparing the resonance wavelengths of NAs by changing the length in transverse direction, blue shifting in resonance wavelengths is observed when the angle of incidence is larger than critical angle. Near-field distribution shows the transverse mode of NAs with TM polarization will always be bright modes in evanescent waves

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In this paper, we observed the extinction spectra of nanoantennas at different incidence angles from 0 degree to 89 degree under prism coupling. The plasmonic dipolar bright and dark mode resonance of gold nanoantennas are clearly observed comparing with the transverse electric (TE) polarized and the transverse magnetic (TM) polarized incident light.

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Effects of silica nanoparticles (NPs) on improving photo-response of Si-based photodiodes (PDs) with surface plasmon resonance (SPR) of Au-Ag NPs have been investigated. The silica NPs can enhance the photo-response by a magnitude of about 1.9 for the wavelength shorter than 650 nm. However the value is reduced to 1.75 for the wavelength longer than 650 nm. In contrast, the reduced photo-response is not found in the 400 oC annealed PDs due to rougher surface.

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To improve the sobility of the nanocomposites in organic solvents, we applied the PEG-NH2 in the synthesis process. The nanocomposites after PEGylation had the amphiphillic property, and we could dope the amphiphillic nanocomposites in the poly(3,4-ethylenedioxythiophene) polystyrene sulfonate and the active layer of the OPVs simultaneously to realized dual plasmonic structures. All the device preformance had been significant improved due to the plasmonic effects.

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The multiple multipole (MMP) method is applied to evaluate quantitatively the electromagnetic field induced by a linearly polarized plane wave illuminating a nanospheroid, and then obtaining the surface traction in terms of Maxwell stress tensor.

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Pure ZnO and Ag–ZnO core–shell nanorods (NRs) were successfully synthesized via a low-temperature hydrothermal method, and as-prepared samples were characterized through low-magnification bright-field TEM image and selected-area electron diffractometry. The enhanced field-emission behavior of Ag–ZnO core–shell NRs along the [0002] crystal c-axis direction and their single-crystalline hexagonal structures were also characterized using surface-protruding Ag nanoparticles. Field-emission results exhibited a low turn-on electric field of 3.93 V/μm and field enhancement factor β of 1593.

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Surface plasmon resonances of Au-Ag nanoparticles (NPs) annealed at various temperatures (100~400 °C) was used to enhance the short wavelength response of silicon-based p-n junction photodiodes (PDs). With increasing annealed temperature of Au-Ag NPs, the short wavelength responsivity increases; however the higher annealed temperature (400 °C) results in a formation of Au-silicide, thus suppressing the responsivity. As compared to the PDs without Au-Ag NPs, the responsivity for the PDs with Au-Ag-NPs annealed at 300 °C is increased by a magnitude of 5.9 at 400 nm wavelength.

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A non-vacuum process for Cu2ZnSnSe4 (CZTSe) thin film solar cells from metal precursors were described. Quaternary kesterite-type Cu2ZnSnSe4 nanoparticles were successfully synthesized by using a relatively simple and different solvent method. Confirmed polyetheramine(D400) solvent capable of increase reaction rate to formed CZTSe nanoparticles than isophorone diamine (IPDA) solution.

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We have proposed a novel design of polarization rotator based on a L-shaped asymmetric hybrid plasmonic waveguide. At λ = 1.55 μm, the polarization efficiency is over 95% as the rotator length is 2.25 μm. In addition, the calculated extinction and insertion loss are 23.03 dB and 2.24 dB, respectively.

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Recently, graphene oxide(GO) has attracted considerable interest. Because it has some unique physical and biomedical characteristics, such as hydrophilic, biocompatibility and structural stability, it affords GO a distinct potential in biomedicine. Hence we combine GO with Cholesteric liquid crystal (CLC) to make vapor sensors for improving the sensitivity and response time of sensors.

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Metal/HfO2/ZnO nanorods (NRs) structures were fabricated for the ultraviolet (UV) photodetector applications. The rectifying factor = 52.28 at ±1V. Under UV light (λ=365 nm), the current increases 2 times higher than the device biased at 1V in dark. The responsivity spectrum shows a good UV/visible ratio = 40.7 under 1V bias.

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ZnO nanowires (NWs) are grown on the ZnO doped Al (AZO) seed layer by a vapor phase transport process. The growth position was varied at 3, 5 and 7 cm. Effects of growth position on the crystallinity, cathodoluminescsnce, and field emission properties of ZnO NWs were studied.

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Gallium nitride (GaN) film of various stress grown by pulsed laser deposition, the stress can be changed by modulating the annealing temperature. If GaN is under compressive stress of 0.78 GPa, the GaN thin film transistor (TFT) has the field effect mobility as large as 211cm2/V-s.

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Effects of texture surface on improving photo-response of Si-based photodiodes (PDs) with surface plasmon resonance (SPR) of Au-Ag NPs have been investigated. Significant SPR is found in the PDs with Au-Ag annealed in 200 oC and 300 oC. The significant SPR causes the photo-response increases from 1.4 to 2.1 with increasing wavelength.

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This work proposes an advanced 3D SOI micro-ring resonator, achieved by wafer adhesive bonding technique. The proposed device exhibits enhanced coupling coefficient between the straight (bus) and ring waveguides, which enables one to design a ring-based, large FSR and box-like passband optical switch without double-resonance issue due to reflection.

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This work reported the fabrication of a composite structure of zinc-oxide/nanoporous-silicon/distributed-Bragg-reflector by using an anodization technique combined with a sol-gel method. Experimental results indicated the developed composite structures had high potential in ultra-violet photodetecing applications.

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