Browsing by Author "Yu, KC"

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10 Gbit/s all-optical non-return to zero-return-to-zero data format conversion based on a backward dark-optical-comb injected semiconductor optical amplifier
(2006-05-15)
Lin, GR
;
Yu, KC
;
Chang, YC
;
光電工程學系
;
Department of Photonics
By using a semiconductor optical amplifier backward injected by a dark-optical-comb pulse train at 10 GHz, we demonstrate a 10 Gbit/s all-optical nonreturn-to-zero (NRZ) to return-to-zero (RZ) format conversion of an incoming optical pseudorandom binary sequence (PRBS) data strieam. Both the polarity and the wavelength of data are conserved during format conversion. Without any preamplification, the extinction ratio of degraded optical NRZ PRBS data is greatly improved from 7.13 to 13.6 dB after NRZ-to-RZ conversion. An ultralow bit-error rate of 10(-12) at a data rate as high as 10 Gbits/s is obtained with a received optical power of-18.3 dBm. The converted RZ PRBS data exhibit a negative power penalty of > 3.7 dB compared with the NRZ PRBS data at a bit-error rate of 10(-12). (c) 2006 Optical Society of America
All-optical pulse data generation in a semiconductor optical amplifier gain controlled by a reshaped optical clock injection
(2006-05-08)
Lin, GR
;
Chang, YC
;
Yu, KC
;
光電工程學系
;
Department of Photonics
Wavelength-maintained all-optical pulse data pattern transformation based on a modified cross-gain-modulation architecture in a strongly gain-depleted semiconductor optical amplifier (SOA) is investigated. Under a backward dark-optical-comb injection with 70% duty-cycle reshaping from the received data clock at 10 GHz, the incoming optical data stream is transformed into a pulse data stream with duty cycle, rms timing jitter, and conversion gain of 15%, 4 ps, and 3 dB, respectively. The high-pass filtering effect of the gain-saturated SOA greatly improves the extinction ratio of data stream by 8 dB and reduces its bit error rate to 10(-12) at -18 dBm. (c) 2006 American Institute of Physics.
Correlation between surface charge accumulation and excitation intensity dependent red-shifted micro-photoluminescence of Si-implanted quartz with embedded Si nanocrystals
(2004)
Lin, CJ
;
Yu, KC
;
Kuo, HC
;
Ou-Yang, MJ
;
Lin, GR
The excitation intensity dependency of nanocrystallite Si (nc-Si) related micro-photoluminescence (mu-PL) from the multi-recipe Si-implanted quartz is characterized. The mu-PL at 724 nm contributed by nc-Si with 3-4 nm diameter is maximized after annealing at 1100degreesC for 3 hours. By increasing the excitation intensity from 10 kW/cm(2) to 300 kW/cm(2), the mu-PLs of 1-hr and 3-hr annealed quartz significantly red-shift from 723 nm to 725 nm and from 724 nm to 735 nm, respectively. This can be explained by the anomalous quantum stark effect due to a surface electric field oriented from photo-ionized nc-Si dots to quartz surface. After 1-hr illumination at power of 300 kW/cm(2), the mu-PL peak wavelength of 3-hr annealed sample is further red-shifted by 2.5 nm. By measuring the accumulated surface charges built up during optical excitation process, the correlation between excitation -intensity dependent PL wavelength red-shift and the photo-ionized nc-Si surface electric-field related quantum stark effect is primarily elucidated.
Pumping intensity dependent surface charge accumulation and redshifted microphotoluminescence of silicon-implanted quartz
(2004-08-09)
Lin, GR
;
Yu, KC
;
Lin, CJ
;
Kuo, HC
;
Ou-Yang, MC
The pumping-intensity dependency of nanocrystallite silicon (nc-Si) related microphotoluminescence (mu-PL) from multirecipe Si-implanted quartz is characterized. After annealing at 1100degreesC for 3 h, themu-PL at 724 nm contributed by nc-Si with a diameter of about 4 nm is maximized. By increasing the pumping intensity from 10 kW/cm(2) to 300 kW/cm(2), the mu-PLs of 1 and 3-h-annealed Si-implanted quartz samples are redshifted by <1.2 and 11 nm, respectively. The mu-PL of 3-h-annealed sample further redshifts by 2.5 nm after pumping at 300 kW/cm(2) for h. Such a redshift in PL is attributed to the anomalous quantum Stark effect under strong illumination, which photoionizes the buried nc-Si and initiates an electric field beneath the surface of Si-implanted quartz. The measurement of accumulating charges and voltage drop during illumination primarily elucidate the correlation between redshift in PL and the photoionized nc-Si induced surface electric field. (C) 2004 American Institute of Physics.
Time-resolved photoluminescence and capacitance-voltage analysis of the neutral vacancy defect in silicon implanted SiO2 on silicon substrate
(2004-09-01)
Lin, GR
;
Lin, CJ
;
Yu, KC
;
光電工程學系
;
Department of Photonics
The nanosecond photoluminescence (PL) dynamics of neutral oxygen vacancy (NOV) defects at 410-460 nm, and less pronounced nanocrystallite Si precursor (E'(delta)) defects at 520 nm in multi-energy silicon-ion-implanted SiO2 (SiO2:Si+) are investigated. The density of NOV defects in as-implanted SiO2:Si+ of 8x10(16) cm(-3) (or 2.5x10(16) cm(-3) calculated from time-resolved PL) is determined by using capacitance-voltage measurement. After annealing at 1100 degreesC for 3 h, the NOV defects are completely activated with a concentration of 4.8x10(17) cm(-3) and a corresponding absorption cross section of 9x10(-17) cm(2). The time-resolved PL lifetime of NOV defects in SiO2:Si+ is significantly shortened from 26 to 3.6 ns and these defects are fully activated after annealing for 3 h. Longer annealing time greatly attenuates the blue-green PL intensity and eliminates the NOV defects, whereas the PL intensity and concentration of E'(delta) defects with lifetime of 20-50 ns increases by a factor of 2. (C) 2004 American Institute of Physics.