Optically pumped middle infrared (Mid-IR) dual wavelength lasers operated at room temperature were demonstrated. Two kinds of InGaAsSb/AlGaAsSb quantum well (QW) with different compositions, which were separated by a thin carrier blocking layer, were grown as active region in a single waveguide laser structure. Dual wavelength at 2.31m and 2.61m were lasing simultaneously when the optically injection is slight higher than the threshold condition.

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The authors demonstrate the transistor cut-off frequency and the base transit time of the LET from 25℃ to 55℃. The cut-off frequency increases and the base transit time decreases with increasing temperature due to the thermionic emission lifetime of quantum-wells at high temperature.

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We report a tunable pulsed optical parametric oscillator using a double-prism domain PPLN as simultaneously an electro-optic Q-switch and a parametric generator in a Nd:YVO4 laser. >2.3-kW peak-power eye-safe light was obtained with this system.

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Broadband terahertz (THz) Emission by two-color laser-induced filament in isotropic media, air and fused silica, are studied by the simulation of transient photocurrent model and experiments. The dependence between several parameters and the THz signal has been checked. The results of air and fused silica are compared and discussed.

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We observed the coherent effect of two kinds of nonlinear frequency conversion process. The fundamental beam (1064nm) and second harmonic beam (532nm) are used to generate the two processes in our simulation. We perform the simulation of frequency conversion by tightly focused Gaussian beam.

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In this work, a light source for high resolution optical coherence tomography system was designed, constructed and studied. The center wavelength of the generated supercontinuum is 1060 nm and the FWHM of the output spectrum can exceed 320 nm. We set up a free space Michelson interferometer with both axial and lateral scanning schemes as a prototype time-domain optical coherence tomography system. The experimentally measured point spread function indicates an axial resolution of <2 μm as compared to a theoretical resolution of <1.6 μm.

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To improve the performance of GaN-based VCSEL, AlGaN/GaN multiple quantum barrier is used to replace the conventional bulk AlGaN electron blocking layer. The laser output power shows significant improvement due to effective electron blocking ability resulted from multiple quantum barrier. This result is also observed by simulating the corresponding structure.

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Malignant neoplasm is the leading cause of death for 30 years in a row in Taiwan. Tumor angiogenesis is a critical factor in the growth and metastasis of most malignant neoplasms and cancer cell is considered to be associated with chemo- and radio-resistance that lead to the failure of therapies. More and more reports have shown that cancer cells can promote tumor angiogenesis and maintain their differentiation with the help of endothelium cells [1]. However, the dynamic interplay between the tumor angiogenesis environment and the growth of cancer cells in vivo is yet a complex unresolved subject. The purpose of this study is to time-course investigate the biology of cancer cells in vivo in the context of tumor angiogenesis. The mCherry regulatory melanoma stable cells were implanted into C57BL/6-c2J mice ears and were in vivo monitored by nonlinear optical microscopy. In order to study the relationship between tumor sizes and vessel permeability, we track the tumor growth in mice and inject the 150-kDa (the radius is about 8 nm) dextran labeled with fluorescein in the different tumor stages to examine the vessel permeability. The result demonstrates that the vessels permeability rate will increase with tumor size.

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We analyze a hybrid plasmonic nanocavity containing a silicon grating NW near a metal surface with a gain gap between. For such cavity with a short cavity length at wavelength λ = 1550 nm, a high quality factor near 550 and ultrasmall modal volume lower than 0.0019 (λ/n)3 are achievable.

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We consider nonresonatly-pumped excitonpolariton condensates in 1-D periodic potential. By analyzing the band structure of the system, we found that gap solitons form at the edge of the Brillouin zones when pumped nonuniformly.

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Dynamical characteristics of semiconductor lasers subject to both optoelectronic feedback and optical feedback are investigated by numerical simulation. The electrical power spectrum of individual system with undesired side peaks resulted from corresponding frequency of the delay loop can be eliminated by the applying another system with different time delay. Furthermore, under proper adjustment of the loop delay time, the main frequencies of power spectrum are changed correspondingly.

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