Browsing by Author "Jyu, Siao-Shan"

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250-GHz Passive Harmonic Mode-Locked Er-Doped Fiber Laser by Dissipative Four-Wave Mixing With Silicon-Based Micro-Ring
(2013-10-01)
Jyu, Siao-Shan
;
Yang, Ling-Gang
;
Wong, Chi-Yan
;
Yeh, Chien-Hung
;
Chow, Chi-Wai
We propose and demonstrate a 250-GHz high-repetition-rate mode-locked Er-doped fiber laser, which utilizes a silicon micro-ring resonator (SMRR). The SMRR acts as an optical comb filter to help achieve passive mode-locking through the dissipative four-wave-mixing effect induced by a piece of high nonlinear fiber. A short section of polarization-maintaining fiber is inserted in the cavity to induce birefringence filtering to significantly enhance the stability of the proposed laser through the combined effects of optical filtering and nonlinear spectral broadening. The laser can operate about 2 and 6 nm in the case of 1.48-ps and 875-fs output pulsewidth, with 3-dB bandwidth, respectively. The laser can remain mode locked, during our measurement time, without any cavity length or temperature feedback control.
300 GHz Bound Pulse Generation in a Filter-Assisted Harmonic Mode-Locked Er-doped Fiber Laser with 20 GHz Phase Modulation
(2014)
Wang, Sheng-Min
;
Jyu, Siao-Shan
;
Lai, Yinchieh
;
光電工程學系
;
Department of Photonics
By inserting a section of PM fiber for birefringence interference filtering with 100 GHz spacing, stable 300 GHz bound pulses have been successfully generated in a harmonic mode-locked Er-doped fiber laser with 20 GHz phase modulation frequency.
A 110 GHz passive mode-locked fiber laser based on a nonlinear silicon-micro-ring-resonator
(2014-06-01)
Yang, Ling-Gang
;
Jyu, Siao-Shan
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Wong, Chi-Yan
Mode-locked fiber lasers have many important applications in science and engineering. In this work, we demonstrate for the first time a 110 GHz high repetition rate mode-locked fiber laser using a silicon-based micro-ring resonator (SMRR) to act as an intra-cavity optical comb filter, as well as an optical nonlinear element. No electrical bias for the SMRR is required to reduce free carrier absorption. The SMRR has a free spectral range of 0.88 nm, enforcing laser mode-locking at the 110 GHz high rate. The optical nonlinearity of the SMRR also supports the dissipative four-wave mixing effect for generating the mode-locked optical pulse trains. The mode-locked pulse-width, optical 3 dB spectral bandwidth and the time-bandwidth product (TBP) are experimentally measured under different pump currents to the erbium-doped fiber-amplifier module inside the laser cavity. The relative intensity noise and the line-width of the proposed laser are also evaluated. Furthermore, a long-term monitoring is performed. The experimental results show that the optical pulse train generated by the SMRR-based mode-locked fiber laser has a 2.6 ps pulse-width (pump current at 400 mA) at a 110 GHz high repetition rate, narrow line-width (1 kHz), high stability (under observation of an hour), and nearly Gaussian transform-limited (TBP is 0.455).
A 110 GHz passive mode-locked fiber laser based on a nonlinear silicon-micro-ring-resonator
(2014-06-01)
Yang, Ling-Gang
;
Jyu, Siao-Shan
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Wong, Chi-Yan
Mode-locked fiber lasers have many important applications in science and engineering. In this work, we demonstrate for the first time a 110 GHz high repetition rate mode-locked fiber laser using a silicon-based micro-ring resonator (SMRR) to act as an intra-cavity optical comb filter, as well as an optical nonlinear element. No electrical bias for the SMRR is required to reduce free carrier absorption. The SMRR has a free spectral range of 0.88 nm, enforcing laser mode-locking at the 110 GHz high rate. The optical nonlinearity of the SMRR also supports the dissipative four-wave mixing effect for generating the mode-locked optical pulse trains. The mode-locked pulse-width, optical 3 dB spectral bandwidth and the time-bandwidth product (TBP) are experimentally measured under different pump currents to the erbium-doped fiber-amplifier module inside the laser cavity. The relative intensity noise and the line-width of the proposed laser are also evaluated. Furthermore, a long-term monitoring is performed. The experimental results show that the optical pulse train generated by the SMRR-based mode-locked fiber laser has a 2.6 ps pulse-width (pump current at 400 mA) at a 110 GHz high repetition rate, narrow line-width (1 kHz), high stability (under observation of an hour), and nearly Gaussian transform-limited (TBP is 0.455).
A new dispersioin measurement apparatus by a periodic wavelengh-scanning pulse laser
(2009)
Jyu, Siao-Shan
;
Liu, Shiou-Fong
;
Hsiang, Wei-Wei
;
Lai, Yinchieh
;
光電工程學系
A new fiber group velocity dispersion (GVD) measurement method has been reported and demonstrated by using a periodic wavelength-scanning pulse laser such as an asynchronously modelocked Er-fiber soliton laser and simple RF spectral measurement.
A simple group velocity dispersion measurement method by RF spectral periodic pulse timing variation characterization
(2009)
Liu, Shiou-Fong
;
Jyu, Siao-Shan
;
Chang, Hon-Chieh
;
Hsiang, Wei-Wei
;
Lai, Yinchieh
By measuring the dispersion-induced periodic pulse timing variation with a wavelength-swept pulse light source and a RF spectrum analyzer, the fiber group velocity dispersion can be determined with excellent accuracy. (C)2009 Optical Society of America
Asynchronous Harmonic Mode Locking in an All-Normal Dispersion Yb-Doped Fiber Laser
(2013-02-01)
Wang, Sheng-Min
;
Jyu, Siao-Shan
;
Hsiang, Wei-Wei
;
Lai, Yinchieh
;
光電工程學系
We present detailed experimental and theoretical results to demonstrate the possibility of asynchronous harmonic mode locking in an all-normal dispersion fiber laser. In contrast to asynchronous soliton mode-locking operation in the anomalous dispersion regime, more profound laser dynamics are found. The experimentally demonstrated 10-GHz asynchronous harmonic mode-locked Yb-doped fiber laser exhibits an excellent super-mode noise suppression ratio in the RF spectrum with picosecond output pulsewidth.
Characteristics of a low repetition rate passively mode-locked Yb-doped fiber laser in an all-normal dispersion cavity
(2013-02-01)
Lin, Ja-Hon
;
Jhu, Jia-Liang
;
Jyu, Siao-Shan
;
Lin, Ting-Chun
;
Lai, Yinchieh
The lasing characteristics of a 365 kHz low repetition rate Yb-doped fiber laser operated in an all-normal dispersion cavity and mode-locked by the nonlinear polarization rotation mechanism are investigated in detail. As the pump power increases, the laser exhibits two transition routes when evolved from the continuous-wave (CW) state to the mode-locked (ML) state. In one evolution route the Q-switched mode-locked (QML) state is sandwiched between the CW and ML states, whereas in the other more interesting evolution route the hysteresis transition between the CW and ML states is found for the first time. Under the mode-locking operation, the laser generates sub-nanosecond pulses with linear dependence of pulsewidth on bandwidth under different pump powers, indicating the presence of giant linear chirps on the laser output pulses.
Characteristics of an Asynchronous Rational Harmonic Mode-Locked Er-Fiber Laser
(2010)
Chang, Chia-Hao
;
Jyu, Siao-Shan
;
Hsiang, Wei. -Wei.
;
Lai, Yinchieh
;
光電工程學系
High repetition rate ultra-short optical pulse trains from an asynchronous rational harmonic mode-locked (ARHML) Er-fiber laser are experimentally demonstrated and studied. This new laser exhibits obvious advantages of pulse amplitude equalization when compared to conventional rational harmonic mode-locked fiber lasers.
Fiber Dispersion Measurement With a Swept-Wavelength Pulse Light Source
(2010-05-01)
Jyu, Siao-Shan
;
Liu, Shiou-Fong
;
Hsiang, Wei-Wei
;
Lai, Yinchieh
;
光電工程學系
A new fiber dispersion measurement method by utilizing a periodically swept-wavelength pulse light source is proposed and demonstrated. The periodic pulse timing variation of the pulse train induced by wavelength sweeping can be directly detected by a radio-frequency spectrum analyzer. Experiments by using an asynchronous mode-locked fiber soliton laser as the swept-wavelength pulse source have been successfully carried out to demonstrate the feasibility.
Laser Dynamics of Asynchronous Mode-locked Fiber Lasers
(2013)
Lai, Yinchieh
;
Jyu, Siao-Shan
;
Wang, Sheng-Min
;
交大名義發表
;
光電工程學系
New laser dynamics of asynchronous mode-locked fiber lasers will be reviewed in details, with the emphases on the interesting repetition frequency pulling effect and the all-normal dispersion operation state of asynchronous mode-locking.
Laser dynamics of asynchronous rational harmonic mode-locked fiber soliton lasers
(2013-08-01)
Jyu, Siao-Shan
;
Jiang, Guo-Hao
;
Lai, Yinchieh
;
光電工程學系
;
Department of Photonics
Laser dynamics of asynchronous rational harmonic mode-locked (ARHM) fiber soliton lasers are investigated in detail. In particular, based on the unique laser dynamics of asynchronous mode-locking, we have developed a new method for determining the effective active modulation strength in situ for ARHM lasers. By measuring the magnitudes of the slowly oscillating pulse timing position and central frequency, the effective phase modulation strength at the multiplication frequency of rational harmonic mode-locking can be accurately inferred. The method can be a very useful tool for developing ARHM fiber lasers.
Multi-Bound Pulse State in a 250 GHz Mode-Locked Fiber Laser Based on a Silicon Micro-Ring Resonator
(2013-01-01)
Jyu, Siao-Shan
;
Yang, Ling-Gang
;
Wong, Chi Yan
;
Yeh, Chien-Hung
;
Chow, Chi-Wai
A 250 GHz passive mode-locked Er-doped fiber laser with a silicon-based micro-ring resonator is demonstrated experimentally. Besides the single pulse operation at 250 GHz, we also observe an interesting multi-bound pulse operation state.
Passive Mode-Locked Er-Fiber Laser with Large Anomalous Dispersion and Nonlinearity
(2010)
Huang, Bo-wei
;
Jyu, Siao-Shan
;
Lin, Ja Hon
;
Lai, Yinchieh
;
光電工程學系
We study the characteristics of a passive mode-locked Er-fiber laser with over 400m single mode fibers inside the cavity to achieve a low pulse repetition rate of 500 kHz and wide optical spectrum of 45nm.
Passive Q-switched mode-locked Er-doped fiber laser with self-similar-like optical spectrum
(2010)
Jyu, Siao-Shan
;
Huang, Bo-wei
;
Lin, Ja Hon
;
Lai, Yinchieh
;
光電工程學系
A self-Q-switched mode-locked Er-doped fiber laser with 500-kHz low mode-locking repetition-rate and peculiar self-similar-like optical spectrum has been experimentally demonstrated. This new operation state may be useful for generating high-peak-power pulses from Er-doped fiber lasers.
Periodically Tapered Long-Period Fiber Gratings by CO2 Laser Heating and Tension Stretching
(2010)
Lu, Po-Hsuan
;
Hsu, Kuei-Chu
;
Jyu, Siao-Shan
;
Lai, Yinchieh
;
光電工程學系
Periodically tapered long-period fiber gratings (LPFGs) are demonstrated by using CO2 laser heating with a cylindrical lens and periodically scanned along the fiber axis on a tensioned standard single-mode fiber. The depth of periodic relief on the fiber surface depends on the writing time as well as the grating period. The LPFG has perfect axial symmetric tapered shape that is helpful for achieving polarization independent properties.
Pulse Repetition Rate Control of Asynchronous Mode-Locked Fiber Lasers without Changing the Cavity Length
(2012)
Jyu, Siao-Shan
;
Lai, Yinchieh
;
光電工程學系
;
Department of Photonics
A new method for fine-controlling the mode-locked laser repetition rate without changing the cavity length is proposed and demonstrated on a 10GHz asynchronous mode-locked Er-fiber soliton laser through the EO modulation strength adjustment.
Repetition frequency pulling effects in asynchronous mode-locking
(2013-02-01)
Jyu, Siao-Shan
;
Lai, Yinchieh
;
光電工程學系
;
Department of Photonics
Repetition frequency pulling effects are found to exist in asynchronous harmonic mode-locked fiber soliton lasers. The deviation frequency of asynchronous mode-locking is found to be dependent on the active modulation depth, not wholly determined by the difference between the intracavity active modulation frequency and the cavity harmonic repetition frequency. Transition from asynchronous to synchronous mode-locking will also occur when the modulation depth is above the threshold. Independent repetition frequency control of asynchronous mode-locked laser can be achieved through the effects. (C) 2013 Optical Society of America
S-band pulse generation by polarization additive-pulse mode-locking in an erbium-doped all-fiber ring laser
(2014-01-01)
Yang, Ling-Gang
;
Jyu, Siao-Shan
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Lai, Yinchieh
An all-fiber S-band mode-locked Er-doped fiber ring laser operated at 1503 nm is experimentally demonstrated by utilizing the polarization additive-pulse mode-locking (P-APM) mechanism. To the best of our knowledge, it is the first P-APM mode-locked fiber laser operating in the S-band. The gain medium is an S-band Er-doped fiber amplifier (EDFA) composed of two Er-doped fiber stages with the technique of depressed-cladding to cut off the fundamental mode. Stable single-pulse operation is achieved within the available pump power range. Besides, characterization of the S-band EDFA module, such as the wavelength dependences of the gain and noise figure, the slope efficiency, as well as the dependence of the pump power on the gain for different input powers is performed. In addition, analysis of the proposed S-band mode-locked fiber laser, such as the pump power dependence of the pulse-width and optical bandwidth, and pulse-width compression is also provided.