共查询到20条相似文献,搜索用时 15 毫秒
1.
Zhi-Ming Liu Jian Li Peng Liu Jing-Jing Zheng Lin-Yong Fan Shui-Sheng Jian 《Optics & Laser Technology》2010,42(8):1261-1265
A simple and effective switchable dual-wavelength polarization-maintaining erbium-doped fiber laser is proposed and demonstrated. Only using a uniform fiber Bragg grating written directly in a segment of the photosensitive and polarization-maintaining erbium-doped fiber as the wavelength selector and an optical circulator as the all-reflecting mirror, a stable simultaneous dual-wavelength oscillation is achieved with a wavelength spacing of 0.364 nm experimentally by exploiting the polarization hole burning effect at room temperature. The output can be switched between single- and dual-wavelength by adjusting the polarization controller. The 3-dB bandwidth and the side mode suppression ratio of the laser’s outputs are measured to be less than 0.01 nm and more than 50 dB. The power fluctuation and wavelength drift are measured to be less than 0.50 dB and 0.020 nm over an hour. 相似文献
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The relationship between the transmitting spectra characteristic of a fused single mode fiber coupler (SMFC) and the performance of interferometric fiber-optic gyroscope (IFOG) is analyzed in theory firstly. Then the transmitting spectra-temperature characteristic of SMFC is experimented, and the influence of the spectrum-stability of the SMFC on IFOG is simulated and experimented. Through the theory analysis and experiment research, it is confirmed that the spectrum output from the SMFC's throughput port is more stable than that output from the coupled port, and the bias instability of the rotation errors induced by the variation of spectrum output from the SMFC's coupled port is 10 times of that output from the throughput port. Therefore, to choose the SMFC's throughput port as the input port for navigation-grade gyroscope is an effective method to improve the IFOG's performance. 相似文献
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We have demonstrated that the gold nanorods (GNRs) can be used as effective saturable absorbers for passively Q-switched erbium-doped fiber laser (EDFL). Two types of GNRs were synthesized by a seed-mediated growth method. The longitudinal surface plasmon resonance wavelengths of the GNRs with different aspect ratios were around 1068 and 1442 nm, respectively. The GNRs were mixed with sodium carboxymethylcellulose (NaCMC) to form GNRs-NaCMC films with different absorption wavelengths. Using these GNRs-NaCMC films, 9.6-μs pulses with a repetition rate of ∼22.9 kHz and 10.4-μs pulses with a repetition rate of ∼22.4 kHz were obtained from the passively Q-switched EDFLs at a pump power of ∼120 mW, respectively. 相似文献
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We propose and demonstrate experimentally a stabilized and wavelength-selective erbium-doped fiber ring laser in single-longitudinal-mode operation with Fabry-Perot laser diode (FP-LD) and using a tunable bandpass filter (TBF) inside and outside a Sagnac ring cavity. The side-mode suppression ratios of 21 dB and 36.5 dB and the output power of -3.6 dB m and -8.7 dB m in the wavelengths of 1524.45-1562.35 nm and 1531.07-1562.35 nm with the tuning step of 1.4 nm can be achieved when the TBF outside and inside Sagnac loop, respectively. The output wavelength variation of zero and the output power fluctuation of <0.1 dB are also obtained. Moreover, the transmission efficiency of the ring laser has also been performed experimentally under a 1.25, 2.5 and 10 Gb/s external modulation, respectively. 相似文献
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Fabrication of single-mode fiber coupler by heating fibers on a flame is very common and popular. However, controlling the input and the output power quantities of the fiber coupling process is neither easy nor similar. Power losses occur at the coupling length as the effect of the geometry and structure of fibers during and after fusion. In application, the power losses will affect sensor devices, e.g. optical switch. This paper proposes power splitting into the second fiber junction as a new model by deriving and integrating the coupling power with two conditions of refractive index changes. First is the change in the vertical part and second is the change in the vertical and the horizontal parts. Both conditions are studied by perpendicular and parallel directions of coupling power. The model is examined with a linear change of refractive index where power absorption and reflection are accumulated by power losses. The result shows that power increases as the effect of losses by simulation. These power losses are lost by radiation out of cladding and fiber heating. 相似文献
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Suchun Feng Ou Xu Shaohua Lu Tigang Ning Shuisheng Jian 《Optics Communications》2008,281(24):6006-6010
A switchable multi-wavelength erbium-doped fiber (EDF) ring laser based on cascaded polarization maintaining fiber Bragg gratings (PMFBGs) in a Sagnac loop interferometer as the wavelength-selective filter at room temperature is proposed. Due to the polarization hole burning (PHB) enhanced by the PMFBGs, stable single-, dual-, three- and four-wavelength lasing operations can be obtained. The laser can be switched among the stable single-, dual-, three- and four-wavelength lasing operations by adjusting the polarization controllers (PCs). The optical signal-to-noise ratio (OSNR) is over 50 dB. 相似文献
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Suchun Feng Ou Xu Shaohua Lu Tigang Ning Shuisheng Jian 《Optics Communications》2009,282(11):2165-4916
Switchable single-longitudinal-mode (SLM) dual-wavelength erbium-doped fiber ring laser based on one polarization-maintaining fiber Bragg grating (PMFBG) is demonstrated. Due to the enhancement of the polarization hole burning (PHB) by the PMFBG, the laser can be designed to operate in stable dual-wavelength or wavelength-switching modes with a wavelength spacing of 0.336 nm at room temperature by adjusting a polarization controller (PC). The stable SLM operation is guaranteed by a compound-ring cavity and a saturable absorber (SA). The optical signal-to-noise ratio (OSNR) is over 45 dB. The amplitude variation in nearly one and half an hour is less than 0.2 dB. 相似文献
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对光纤激光极限功率的探索和其受限因素的分析, 有利于为大功率光纤激光器的发展提供理论依据和实验指导. 本文考虑热效应、光效应、非线性效应和抽运亮度等因素对光纤激光极限功率的影响, 分析了掺镱和掺铥光纤的极限功率和受限因素. 在此基础上, 结合激光在光纤中单模传输的条件, 计算了单模掺镱和掺铥光纤激光的极限功率. 计算结果表明, 在现有技术条件下, 使用常规的976 nm和793 nm激光二极管抽运, 单模掺镱和掺铥光纤激光的极限功率分别为4.2 kW和7.8 kW, 其中单模掺铥光纤激光的功率水平还远低于它的极限功率的原因是受抽运亮度的限制. 最后分析指出减小纤芯的数值孔径和改进少模光束的光束质量是提升单模光纤激光极限功率的重要途径. 相似文献
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We demonstrated a tunable Q-switched ytterbium-doped fiber laser (YDFL) using MoWS2/rGO nanocomposite as passive saturable absorber. Further, the Mo1?xWxS2/rGO nanosheets, with x proportion of 0.2, are synthesized using hydrothermal exfoliation technique. The proposed nanocomposite-PVA based thin film is fabricated by mixing the MoWS2/rGO nanosheets with polyvinyl alcohol (PVA). The fabricated thin film is sandwiched between two fiber ferrules to realize the proposed saturable absorber (SA). Further, the proposed MoWS2/rGO-PVA based thin film SA exhibits a fast relaxation time and a high damage threshold which are suitable to realize a Q-switched pulsed laser with a tunable wavelength range of 10?nm that extends from 1028?nm to 1038?nm. For the highest pump power of 267.4?mW, the generated Q-switched pulses exhibit a narrow pulse width of 1.22 μs, the pulse repetition rate of 90.4?kHz, the highest pulse energy of 2.13?nJ and its corresponding average power of 0.193?mW. To the best of author’s knowledge, this is the first realization of a tunable Q-switching fiber laser in a 1?μm wavelength using MoWS2/rGO nanocomposite saturable absorber. 相似文献
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Suchun Feng Ou Xu Shaohua Lu Xiangqiao Mao Tigang Ning Shuisheng Jian 《Optics & Laser Technology》2009,41(3):264-267
A switchable erbium-doped fiber-ring laser providing dual-wavelength outputs with orthogonal polarizations when operating at room temperature is proposed. One polarization-maintaining fiber Bragg grating (PMFBG) in a Sagnac loop interferometer is used as the wavelength-selective filter. Due to the enhancement of the polarization hole burning (PHB) by the PMFBG, the laser can be designed to operate in stable dual-wavelength or wavelength-switching modes with a wavelength spacing of 0.336 nm at room temperature by adjusting a polarization controller (PC). The optical signal-to-noise ratio (OSNR) is over 42 dB. The amplitude variation over 90 min is less than 0.6 dB for both wavelengths. 相似文献
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研制出光敏偏振保持掺Er3+光纤,通过在这种光纤上紫外写入三个光纤光栅,形成对抽运激光高转化效率的谐振腔.在输出功率为23.617dBm、工作波长为976nm的激光抽运下,得到均值功率为9.20dBm、均值中心波长为1554.554nm的单波长激光输出.在室温下800min(约13.3h)的测量时间内,其输出功率的波动为±0.05dB,中心工作波长的波动为±0.0015nm.
关键词:
光纤激光器
3+光纤')" href="#">偏振保持掺Er3+光纤
光纤Bragg光栅 相似文献
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A wavelength tunable erbium-doped fiber ring laser with flattened output power spectrum over a broadband is proposed and demonstrated. The power flattening is achieved using a high-birefringence fiber loop mirror, in which a number of high-birefringence fiber sections and polarization controllers are used to get a reflection spectrum that can compensate for the output power spectrum. The wavelength tuning is realized by compressing or stretching the FBGs in the laser cavity. A 1×3 switchable fiber Bragg grating array is incorporated into the fiber ring to get a wideband tuning range of 38 nm, from 1527 to 1565 nm. Within this range, the output power uniformity is controlled within ±0.8 dB. The total output power is about 4 dBm, the 3-dB linewidth is 0.01 nm, and the side mode suppression ratio is more than 48 dB. 相似文献
16.
Yang Shiquan Zhao Chunliu Meng Hongyun Ding Lei Dong Xiaoyi Yuan Shuzhong Kai Guiyun Zhao Qida 《Optical and Quantum Electronics》2003,35(1):69-73
We describe a novel erbium-doped fiber ring laser utilizing the backward amplified spontaneous emission (ASE) power as a secondary pump source so that it can operate in L-band stably. The output wavelength can be tuned in a wide range of 45 nm, from 1560 to 1605 nm. We also compared this scheme with the condition of not using the ASE as secondary pump source, and found this scheme could improve the performance of the laser when using the same components. 相似文献
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In this paper, we present and propose a novel structure for improved birefringence and single-mode propagation condition photonic crystal fiber (PCF) in a broad range of wavelength. The birefringence of the fundamental mode and single mode property in such a PCF is numerically estimated by employing full vector finite element method (FVFEM) and anisotropic perfectly matched layers (APML). The simulation results illustrate that we can achieve a high birefringence and perfect single-mode condition by employing silica-filled into one-line elliptical air holes parallel to x-axis and rotated by an angle. Obviously, the proposed PCF is quite useful for optical devices. 相似文献
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The temporal characteristics of the Q-switched Nd-glass laser have been numerically investigated. A mathematical model describing the dynamic emission and different physical processes has been adapted. This model allows the investigation of the nonlinear saturable absorber effects on the mode characteristics of the Nd-glass laser, and studying the affects of the laser input parameters on the output laser pulse characteristics.Numerical solutions of a nonlinear rate equation system predict the generation of nanosecond pulses of Q-switched Nd-glass laser. The solutions estimate the laser density and the relative population inversion of the Nd-glass laser rod and saturable absorber for different emission regimes. The estimated results of the laser output pulse characteristics are in a good agreement with the other calculated and experimental results. 相似文献
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Zernike polynomials have been widely used for wave-front analysis because of their orthogonality over a uniform circular pupil. However, the pupil is not uniform but weighted by the backpropagated fiber mode in analyzing fiber coupling efficiency. Zernike polynomials are not appropriate for a weighted pupil due to their lack of orthogonality over such pupil. We emphasize the advantages of using orthonormal polynomials in fiber coupling systems. The orthonormal polynomials over weighted pupil are derived by matrix approach. The effects of primary aberrations are investigated based on the orthonormal polynomials. The accuracy of the Strehl ratio approximation for primary aberrations is evaluated. 相似文献
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A tapered graded-index fiber (GIF) structure is, for the first time, proposed for the efficient fiber-laser coupling. A simple analytical approach based on the ABCD law is utilized to optimally design the parameters of the hemispherically-ended GIF taper. A wide-angle beam propagation method is then employed to compute the fiber mode fields transmitted through the fiber taper in order to evaluate the coupling efficiency. By taking one commercially available GIF as an example, the effectiveness of the new design reported here is verified with a demonstration of high coupling efficiency of nearly 90%. 相似文献