Browsing by Author "Lin, Sung-Hui"

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Chirped-pulse control of carrier dynamics in low-temperature grown GaAs
(2011)
Lee, Chao-Kuei
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Lin, Sung-Hui
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Yang, C. S.
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Pan, Ci-Ling
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物理研究所
In this work, using chirped pulse excitation pump-probe technique, we present the results of a study of carrier dynamics modulation in low-temperature-grown GaAs. Increasing carrier relaxation times as varying the excitation chirped conditions from negative to positive is demonstrated and explained by spectral dependence of carrier dynamics in Shockley-Read Hall model. We also indicate that chirped pulse has the feasibility of controlling carrier dynamics in ultrafast optical devices.
Chirped-pulse manipulated carrier dynamics in low-temperature molecular-beam-epitaxy grown GaAs
(2014-04-28)
Lee, Chao-Kuei
;
Lin, Yuan-Yao
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Lin, Sung-Hui
;
Lin, Gong-Ru
;
Pan, Ci-Ling
Chirped pulse controlled carrier dynamics in low-temperature molecular-beam-epitaxy grown GaAs are investigated by degenerate pump-probe technique. Varying the chirped condition of excited pulse from negative to positive increases the carrier relaxation time so as to modify the dispersion and reshape current pulse in time domain. The spectral dependence of carrier dynamics is analytically derived and explained by Shockley-Read Hall model. This observation enables the new feasibility of controlling carrier dynamics in ultrafast optical devices via the chirped pulse excitations. (C) 2014 AIP Publishing LLC.
Enhancement of broadband Terahertz Radiation by carrier dynamics modulation with a single chirped optical pulse
(2008)
Lee, Chao-Kuei
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Lin, Sung-Hui
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Pan, Ci-Ling
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光電工程學系
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Department of Photonics
Over 60% enhancement of broadband THz radiation and two-fold bandwidth broadening are demonstrated by a single positive chirped optical pulse. A model of carrier dynamics modulation is proposed to explain this phenomenon. (C) 2008 Optical Society of America
Optical properties and potential applications of epsilon-GaSe at terahertz frequencies
(2009-09-01)
Chen, Ching-Wei
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Tang, Tsung-Ta
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Lin, Sung-Hui
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Huang, Jung Y.
;
Chang, Chen-Shiung
Ordinary and extraordinary refractive indices of an epsilon-GaSe crystal at terahertz (THz) frequencies are experimentally determined in this study. Fitting experimental data by THz time-domain spectroscopy (THz-TDS) and a Fourier transform infrared spectrometer (FTIR), we proposed revised complex dielectric functions and Sellmeier equations of GaSe for both ordinary and extraordinary waves from 0.2 to 100 THz. Phonon vibrational modes and overtones in the THz frequency range are examined in detail. The high magnitude of the figure of merit (FOM similar to 10(3) at 1 THz), the large birefringence (Delta n similar to 0.76 at 1 THz). and the low absorption coefficient (alpha similar to 0.2 cm(-1) at 1 THz) of GaSe are also identified. Potential applications to practical photonic devices such as phase shifters at THz frequencies are proposed. (C) 2009 Optical Society of America