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Chan-Shan Yang, Chia-Jen Lin, Ru-Pin Pan, Christopher T. Que, Kohji Yamamoto, Masahiko Tani, and Ci-Ling Pan Department of Physics, National Tsing Hua University, No. 101, Section 2, Kuang Fu Road, Hsinchu, Taiwan 30013, China Department of Electrophysics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu, Taiwan 30010, China Research Center for(More)
We analyze the dynamic behaviors of a novel device, i.e., cascaded high-speed laser power converters (LPCs), which can detect the direct-current (dc) component of an incoming high-speed optical data stream and efficiently convert its dc component to dc electrical power. By utilizing a p-type photoabsorption layer in our LPC, the problem of slow-motion holes(More)
A comparative study of indium-tin-oxide (ITO) nanowhiskers (NWhs) and thin films as transparent conductors in the terahertz frequency range are conducted. We employ both transmission-type and reflection-type terahertz time-domain spectroscopies (THz-TDTS and THz-TDRS) to explore the far-infrared optical properties of these samples. Their electrical(More)
Indium-tin-oxide nanowhiskers were employed as transparent electrodes in a liquid-crystal terahertz phase shifter. Transmittance of the device was as high as ∼75%. Phase shift exceeding π/2 at 1.0 THz is achieved in a ∼500  μm-thick cell. The driving voltage required for the device operating as a quarter-wave plate was as low as 17.68 V (rms), an(More)
Indium-tin-oxide (ITO) nanowhiskers with attractive electrical and anti-reflection properties were prepared by the glancing-angle electron-beam evaporation technique. Structural and crystalline properties of such nanostructures were examined by scanning transmission electron microscopy and X-ray diffraction. Their frequency-dependent complex conductivities,(More)
We demonstrate novel GaAs/In<sub>0.5</sub>Ga<sub>0.5</sub>P high-speed laser power converters (LPCs), which not only can detect the envelope of incoming high-speed optical data but also can efficiently convert its optical dc component to dc electrical power. By utilizing the graded p-type GaAs and n-type In<sub>0.5</sub>Ga<sub>0.5</sub>P layers as(More)
Indium-tin-oxide (ITO) nanorods (NRs) and nanowhiskers (NWhs) were fabricated by an electron-beam glancing-angle deposition (GLAD) system. These nanomaterials are of interests as transparent conducting electrodes in various devices. Two terahertz (THz) time-domain spectrometers (TDS) with combined spectral coverage from 0.15 to 9.00 THz were used. These(More)
We describe in detail the characterization of two high-power photonic transmitters based on two different kinds of high-power photodiodes, one a GaAs/AlGaAs based uni-traveling-carrier photodiode (UTC-PD) and the other a separated- transport-recombination photodiode (STR-PD). The diodes operate under optical pulse excitation at the 800 nm wavelength. Both(More)
Quarter-wave operation or a phase shift of more than &#x03C0;/2, which is approximately ten times greater than that reported in previous works using liquid crystals (LCs) and graphene electrodes, was demonstrated. The device is transparent to the terahertz (THz) wave, and the driving voltage required was as low as approximately 2.2 V (rms), which is also(More)
Terahertz (THz) radiation can be generated more efficiently from a low-temperature-grown GaAs (LT-GaAs) photoconductive (PC) antenna by considering the two-photon absorption (TPA) induced photo-carrier in the photoconductor. A rate-equation-based approach using the Drude-Lorentz model taking into account the band-diagram of LT-GaAs is used for the(More)