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1.
We report on the experimental observation of soliton pulses in an
erbium doped fibre ring laser. The passive mode-locking is achieved
using the nonlinear polarization rotation technique. By adjusting the
pump power and the intracavity polarization controllers, a normal
soliton, a stable 8th harmonic mode-locked pulse and a noise-like
pulse have been observed in our laser. The experimental results
revealed that the noise-like pulse is not suitable for the optical
telecommunication, and in order to obtain the stable harmonic
mode-locked soliton, a strong unstable CW laser field is necessary to
mediate global soliton interaction. The formation mechanism of the
harmonic mode-locked pulse has also been analysed. 相似文献
2.
We demonstrate generation of supercontinuum pulses directly from a passively mode-locked long-cavity fiber ring laser. The laser output exhibited a blueshifted spectrum extending from 1350 to 1550 nm with an average output power greater than 60 mW. 相似文献
3.
The advantages of using nonlinear optical loop mirror (NOLM) to compress pulse with slight amplitude fluctuation and reflected energy loss are analyzed in theory. Experimentally the NOLM is placed in an actively mode-locked erbium-doped fiber ring laser to form a figure-eight actively and passively mode-locked fiber laser. 12 ps mode-locked pulses centered at 1.543 μm were obtained with the modulation frequency of 2.498748700 GHz. 3.715 mW output power is achieved with 50 mW pump power. 相似文献
4.
Exploiting the nonlinear polarization rotation technique and adjusting the polarization controllers orientations and the pump power, we achieved stable operations of Q-switched mode-locked or CW modelocked regimes in an ytterbium-doped fibre laser with a unidirectional ring cavity containing a polarizer placed between two in-line polarization controllers. Numerical simulations of pulse propagation in such a modelocked fibre ring laser are performed, which reveals that the Q-switched mode-locked or CW mode-locked regimes can be achieved by aligning the polarizer near the slow or the fast axes of the fibre. 相似文献
5.
6.
Generation of 10-GHz duty-cycle tunable square optical pulse in an SOA-based mode-locked fiber laser
We demonstrate the generation of 10-GHz optical square pulses by injecting a picosecond pulse train into an SOA-based mode-locked
fiber laser. The novel scheme exploits nonlinear effects and gain saturation phenomenon in the semiconductor optical amplifier
(SOA). This technique uses gain-compression dynamics between the input pulses and the generated ones in gain-saturated SOA
to form square pulses. The center wavelength of the generated optical square pulse can be tuned from 1530 to 1570 nm by adjusting
the center wavelength of the optical band pass filter (OBPF) in the SOA-based mode-locked fiber ring laser. The duty cycle
of the output pulse can be tuned from 12.7 to 88.4%, which strongly depends on the input power and intra-cavity power. 相似文献
7.
Influence of the bias current on the output characteristics of a mode-locked fiber ring laser consisting of two SOAs 总被引:2,自引:0,他引:2
In this paper, after obtaining the mode-locked pulse shape with self-reproduction theory, the influence of the bias current on the output characteristics of a backward-optical-injection harmonic mode-locked fiber ring laser consisting of two semiconductor optical amplifiers (SOAs) has been numerically investigated. The results show that the mode-locked pulse with high peak power and narrow width can be obtained through reasonably adjusting the bias currents of the two SOAs. 相似文献
8.
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10.
Fei Wang 《Optics & Laser Technology》2011,43(4):848-851
A stable multiwavelength mode-locked semiconductor fiber ring laser incorporating a fiber Mach-Zehnder interferometer (MZI) filter was proposed and experimentally demonstrated. A semiconductor optical amplifier (SOA) serves as an optically controlled mode-locking element due to gain exhaustion caused by external injected optical pulses. Another SOA severs as a constant-gain medium. A fiber MZI filter with a temperature control is incorporated into the fiber ring cavity to acquire a stable and tunable multiwavelength oscillation. Twelve wavelengths are synchronously mode-locked at 10 GHz, pulse width of mode-locked pulse are about 30 ps. Proposed multiwavelength mode-locked semiconductor fiber ring laser has some distinct advantages, such as simple and compact structure, easy integration, convenient tuning, good stability, potential high repetition rate operating, which has potential application in the future WDM communication system. 相似文献
11.
Yoshitomi D Kobayashi Y Kakehata M Takada H Torizuka K Onuma T Yokoi H Sekiguchi T Nakamura S 《Optics letters》2006,31(22):3243-3245
The pulse timing of a mode-locked Er-doped fiber laser was stabilized to a reference pulse train from a Cr:forsterite mode-locked laser by all-optical passive synchronization scheme. The reference pulses were injected into a ring cavity of the fiber laser by using a 1.3-1.5 mum wavelength-division multiplexer. The spectral shift induced by cross-phase modulation between copropagating two-color pulses realizes self-synchronization due to intracavity group-delay dispersion. The rms integration of timing jitter between the fiber laser pulse and the reference pulse was 3.7 fs in a Fourier frequency range from 1 Hz to 100 kHz. 相似文献
12.
We report on the operation of a passively mode-locked fiber ring laser made of purely normal dispersive fibers. Self-started mode locking can still be achieved in the laser by use of the nonlinear polarization rotation technique, and the mode-locked pulse has large pulse energy, strong frequency chirp, and a mode-locked spectral width limited by the effective laser gain bandwidth. Furthermore, we show that the operation of the laser can be well described by an extended Ginzburg-Landau equation model that governs the soliton dynamics of fiber lasers. 相似文献
13.
We present a multi-wavelength mode-locked fiber ring laser incorporating a semiconductor optical amplifier (SOA) and a Fabry-Perot semiconductor optical amplifier (FP-SOA). Because the gain of the SOA is depleted by an external injection optical signal, the SOA acts as a loss modulator. The FP-SOA serves as a tunable comb filter. The presented laser source can generate 19 synchronized wavelength channels with the extinction ratio of about 21 dB, each mode-locked at 10 GHz, and mode-locked pulse width is about 40 ps. Oscillation wavelengths band can be tuned by adjusting the bias current of the SOA, and wavelength spacing also can be changed by using a tunable optical delay line (ODL) or a temperature controller. The polarization-insensitive devices ensure that the output power is rather stable. This fiber laser has potential applications in longer waveband (L-band) within the low-attenuation window. 相似文献
14.
8字形主被动锁模掺Er3+光纤激光器 总被引:6,自引:0,他引:6
在理论上分析了利用非线性光学环形镜作为等效可饱和吸收体压缩脉冲进行锁模的物理机制。利用8字形主被动混合锁模的结构在调制频率2.498749GHz下,在1.543μm处获得了12ps的锁模脉冲输出,对应谱宽0.22nm,时间脉宽积0.33。在抽运功率50mW情况下,输出脉冲平均功率3.715mW。在调制频率2.499344GHz、2.499114GHz和2.498999GHz时分别并获得了2~4阶幅度较为均衡的有理数谐波锁模脉冲序列。 相似文献
15.
利用光纤的非线性偏振旋转效应产生可饱和吸收体的锁模机制,从掺Yb3+光纤环形激光器中得到稳定高阶谐波锁模光脉冲。理论分析了工作于正色散区的掺Yb3+光纤环形激光器的特性。实验中观测到了掺Yb3+光纤环形激光器3种不同演化方式产生高阶锁模光脉冲。4阶谐波锁模脉冲(107.2 MHz重复频率)经过1 m长高掺杂Yb3+光纤放大器放大后产生了平均功率100 mW,脉宽22.8 ps的脉冲,最后经过光栅压缩得到了平均输出功率20 mW,脉宽307 fs,脉冲中心波长1 051.2 nm,带宽13.76 nm的激光。 相似文献
16.
We experimentally demonstrate the operation of a passively mode-locked Raman fiber ring laser with an ultrahigh repetition rate of 100 GHz and up to 430 mW of average output power. This laser constitutes a simple wavelength versatile pulsed optical source. Stable mode locking is based on dissipative four-wave mixing with a single fiber Bragg grating acting as the mode-locking element. 相似文献
17.
An actively mode-locked fiber ring laser based on cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA) is demonstrated to operate stably with a simple configuration. By forward injecting an easily-generated external pulse train, the mode-locked fiber laser can generate an optical-pulse sequence with pulsewidth about 6 ps and average output power about 7.9 mW. The output pulses show an ultra-low RMS jitter about 70.7 fs measured by a RF spectrum analyzer. The use of the proposed forward-injection configuration can realize the repetition-rate tunability from 1 to 15 GHz for the generated optical-pulse sequences. By employing a wavelength-tunable optical band-pass filter in the laser cavity, the operation wavelength of the designed SOA-based actively mode-locked fiber laser can be tuned continuously in a wide span between 1528 and 1565 nm. The parameters of external-injection optical pulses are studied experimentally to optimize the mode-locked fiber laser. 相似文献
18.
We report on the generation of noise-like pulses with up to 120 nm bandwidth in a passively mode-locked erbium-doped fiber ring laser. By inserting a segment of slightly normal dispersion fiber in a mode-locked fiber laser cavity, we found that the spectrum of the noise-like pulse emission of the laser can be significantly broadened as a result of the four-wave-mixing and the soliton self-frequency shift effects in the inserted fiber. 相似文献
19.
讨论了自启动被动锁模掺Yb3+光纤环形激光器产生短脉冲的机理,并研制出全光纤结构超短脉冲掺Yb3+光纤环形激光器.采用两个976nm半导体激光器级联抽运作为抽运源,高掺杂浓度掺Yb3+光纤作为增益介质,利用光纤的非线性偏振旋转效应,得到自启动、十分稳定的ps量级锁模光脉冲.激光器锁模阈值功率260mW,输出功率25mW,锁模光脉冲中心波长1056nm,3dB带宽11.7nm,重复频率20MHz.与其他结构光纤激光器相比,这种全光纤结构具有更高的效率和更好的稳定性.
关键词:
环形光纤激光器
3+光纤')" href="#">高掺杂浓度掺Yb3+光纤
自启动
被动锁模 相似文献
20.
The transition state between the continuous wave region and the mode-locked region in a passively mode-locked erbium-doped fibre ring laser has been experimentally observed by utilizing the nonlinear polarization rotation technique.When the pump power reaches the mode-locked threshold,the metastable pulse train with a tunable repetition rate is obtained in the transition from the continuous wave state to the passive mode-locked state via proper adjustment of the polarization controller.A simple model has been established to explain the experimental observation. 相似文献