共查询到18条相似文献,搜索用时 46 毫秒
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提出了一个基于自激发受激布里渊散射的波长间隔可变多波长光纤激光器.利用单模光纤中自激发产生的非线性布里渊增益和掺铒光纤的线性增益组成混合增益光纤激光器,从而使光纤激光器在室温下产生稳定的多波长输出.改变双折射光纤环镜滤波器中保偏光纤的长度,可以实现波长间隔可变多波长激光产生,提高了多波长光纤激光器操作的灵活性和实用性.实验实现了波长间隔从0.8 nm至0.076 nm可变的多波长激光产生,波长数随波长间隔减小而增加,间隔为0.08 nm的激光波长数达86. 相似文献
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许磊;马万卓;王天枢;张鹏;孔梅;张靓 《光子学报》2015,44(9):906003-906003
设计了一种无反馈全开腔双倍间隔布里渊-喇曼光纤激光器.采用C+L波段可调谐激光器作为布里渊泵浦,中心波长为1455nm的激光二极管作为喇曼泵浦,7km色散补偿光纤作为增益介质.受激布里渊散射和喇曼放大在色散补偿光纤中同时产生,奇数阶和偶数阶斯托克斯光分别从色散补偿光纤两端输出.该结构减少了多个器件造成的插入损耗.最多可得到186个波长数,调谐范围为28.6nm,波长间隔为0.154nm.加入一段4m掺铒光纤优化后可将边模抑制比从14dB提高至20dB. 相似文献
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提出了一种多波长窄线宽光纤放大器,其种子光由多个单频激光耦合而成,所有单频激光波长几乎相等(波长间隔小于1 nm),频率间隔大于两倍布里渊频移。建立了此类多波长窄线宽光纤放大器的完整理论模型,分析了放大器中受激布里渊散射(SBS)与种子数目的关系。搭建了双波长和三波长窄线宽光纤放大器,进行SBS阈值输出功率测定实验。实验结果与理论模拟结果基本一致,验证了理论模型的合理性;双波长和三波长放大可以有效抑制SBS效应,大幅提高放大器输出功率。 相似文献
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为了获得不同间隔双波长信号输出,提出一种基于受激布里渊效应产生双波长激光的实验装置,利用不同间隔双波长输出信号进行拍频实验可获得可调的微波信号输出;利用一段10 km长普通单模光纤(SMF)作为布里渊增益介质,一个线宽为5 kHz分布反馈激光器(DFB)作为布里渊抽运源,一段未泵浦的保偏掺铒光纤用作饱和吸收体抑制边模,通过改变未泵浦保偏掺铒光纤的长度,可获得不同间隔输出的双波长光纤激光器,实验获得波长间隔为0.170 nm和0.085 nm的激光信号输出,分别对应20 GHz和10 GHz的微波信号。 相似文献
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A novel technique of producing multiwavelength laser source was described utilising a linear cavity of hybrid Brillouin/Erbium fibre laser (BEFL). Twenty-two stable output lasers with 10.88 GHz line spacing were obtained from this architecture at 1557.5 nm that was at the peak of Erbium gain. The requirement of an internal feedback that is commonly used in a ring configuration to generate cascaded Brillouin Stokes for multiple wavelengths operation was achieved by the proposed linear cavity design. 相似文献
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We have demonstrated a tunable multiwavelength self-seeded Brillouin-erbium fiber laser (BEFL) without externally Brillouin pumping. In this scheme, the stable multiwavelength comb can be produced within a ∼45-nm wavelength tuning range through adjusting the polarization controllers (PCs) in a high-birefringent Sagnac loop mirror. The generation of ∼200-line Stokes comb has been achieved by adjusting PCs under bidirectional pumping of two laser diodes, which is the largest wavelength number to the best of our knowledge. The effect of 980 nm pump power on the multiwavelength generation was also investigated. 相似文献
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A stable and compact multi-wavelength Brillouin fiber laser (BFL) operating at room temperature is experimentally demonstrated using a 100 m long photonic crystal fiber (PCF) in conjunction with a figure-of-eight configuration. At a Brillouin pump (BP) level of 15.3 dBm, 7 simultaneous lines with 20 GHz or 0.16 nm line spacing is achieved by removing the odd-order Stokes lines. The anti-Stokes lines are also generated via four wave mixing process in the laser cavity. Compared with the Erbium-based multi-wavelength laser, this BFL has advantages in term of channel spacing and flexibility in the choice of operating wavelength. The output spectrum of the proposed BFL can be tuned by 80 nm, dependent on the availability of an appropriate BP source. The multi-wavelength BFL shows a good stability with power fluctuations of less than 0.5 dB over more than 3 h. 相似文献
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YANG Qian;ZHOU Zezhong;ZHANG Zuxing 《光子学报》2022,51(12):56-63
Because of their outstanding advantages of high power, high efficiency, multi-wavelength, tunable, narrow linewidth, and variable bandwidth, fiber lasers based on random distributed feedback have a broad development prospect in the exploration of new light sources. Random fiber lasers based on Rayleigh scattering distributed feedback are widely studied and discussed by scholars. As a result, they can overcome the disadvantages of traditional distributed feedback random lasers such as a complex structure, large cavity loss, low output laser efficiency, spectral instability, and low practicality. In recent years, several research reports on random fiber lasers have widely applied the combination of Stimulated Brillouin Scattering(SBS), Stimulated Raman Scattering(SRS), and Rayleigh Scattering(RS) to achieve multi-wavelength cascaded output. A single multi-wavelength Brillouin-Raman random fiber laser with tunable frequency spacing is innovative and worthy of further exploration, considering the lack of flexibility and limited applications of multi-wavelength output at a fixed frequency interval. In this paper, the cavity loss is controlled by tuning the attenuator in the reflection ring, which makes the laser cavity structure switch between a semi-open cavity and a full-open cavity. What's more, the frequency interval of multi-wavelength output can also be switched by this way. Compared to other multi-wavelength fiber lasers with switchable frequency intervals, this structure is more simple and has a wider output bandwidth.In the current laser configuration, the multi-wavelength cascade output is the result of a combination of SBS, RS, and SRS at high Raman Pumping (RP) power. The RP produces a distributed Raman gain in the DCF and then amplifies the BP. When the BP power satisfies the SBS threshold, a back-propagating first-order Brillouin Stokes Light (BSL) is generated. Similarly, the first-order BSL is also amplified by the distributed Raman gain and acts as a new pump source to generate a second-order BSL that propagates backwards with respect to the first-order BSL. Thus, the lower-order BSLs act as a pump source to generate more higher-order BSLs, and such a cascade process will continue until the overall gain is insufficient to offset its losses. The switchable frequency interval of multi-wavelength output is achieved by tuning the attenuator in the reflective ring 2, which can precisely control the power of the reflected signal entering the cavity. When the attenuation is small, the multi-wavelength output has a single-frequency interval, and when the attenuation is large, the multi-wavelength output has a double-frequency interval.The influence of changing the attenuation in reflection ring 2 on the Peak Power Difference (PPD) between adjacent Stokes lines is discussed in the experiment. When the attenuation is small, most of the even-order BSLs propagating to the right are reflected into the fiber through the reflective ring 2, and then combine with the odd-order BSLs propagating to the left. As a result, the laser produces Stokes lines with a single-frequency interval, at which time the spectral flatness is less than 3 dB, satisfying the condition of producing BSLs with a frequency interval of ~10 GHz. Continuing to increase the attenuation, the frequency interval of adjacent Stokes lines is in the transition from ~10 GHz to ~20 GHz, while the PPD is also changing in the range of 3 dB to 20 dB. When the even-order BSLs propagating to the right are almost all attenuated, the laser produces Stokes lines with a double-frequency interval, and only the even-order Rayleigh components propagate together with the odd-order BSLs. Under this circumstance, the PPD is more than 20 dB and almost constant, which satisfies the condition of producing BSLs with a frequency interval of 20 GHz. The influence of BP wavelength and power on the multi-wavelength output is further discussed in the experiment. The best result is obtained under the optimal experimental conditions, at which multi-wavelength outputs with a single-frequency interval (~10 GHz) in wavelength range of 39 nm (1 532 ~1 571 nm) and multi-wavelength output with a double-frequency interval (~20 GHz) in wavelength range of 39.5 nm (1 532 ~1 571.5 nm) are obtained.A frequency interval switchable multi-wavelength Brillouin-Raman random fiber laser based on cavity loss modulation is proposed and demonstrated. The random fiber laser based on the random distributed feedback is formed by RS combined with nonlinear effects such as SBS and SRS to achieve multi-wavelength cascaded output. Further by controlling the attenuation of the tunable attenuator in the reflective ring 2, the cavity structure is switched between a semi-open cavity and a full-open cavity, which makes the frequency interval and optical signal-to-noise ratio of the multi-wavelength output switchable. The experimental results show that when the attenuation is -2 dB, the multi-wavelength output with a single-frequency interval (10.48 GHz) in a wavelength range of 39 nm (1 532 ~1 571 nm) can be obtained, and the optical signal-to-noise ratio is 17.2 dB at this time. When the attenuation is -30 dB, the multi-wavelength output with a double-frequency interval (20.96 GHz) in a wavelength range of 39.5 nm (1 532 ~1 571.5 nm) can be obtained, and the optical signal-to-noise ratio is 25.2 dB at this time. Compared to other multi-wavelength fiber lasers with switchable frequency intervals, this structure is simpler and has a wider output bandwidth. 相似文献
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An all-optically generated millimeter wave carrier at 21.7 GHz, 43 GHz and 64.45 GHz are experimentally achieved. These frequencies are realized by generating two consecutively laser wavelengths and are detecting on the 70 GHz high-speed photo detector (HSPD). The initial mixing between the Brillouin pump and the second-order Stokes wavelengths is spaced by 0.178 nm. This spacing, which is doubled from an inherently generated Stokes shift, is accomplished through an isolated circulation of the first order Stokes wave in the double Brillouin Stokes shifter (DSBS) built with 25-km single mode fiber. The generated millimeter carrier is measured at 21.7 GHz, 43 GHz and 64.4 GHz achieved with BP power of 11 mW, 30 mW and 47 mW, respectively. 相似文献
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In this paper we propose and demonstrate an S-band Brillouin-Raman Fiber Laser (BRFL). The S-band BRFL utilizes a Dispersion Compensating Fiber (DCF) as the non-linear gain medium in a linear cavity configuration and amplified by two 1425 nm, 380 mW pumped Raman Fiber Amplifiers (RFAs). A Brillouin Pump (BP) signal of 1515 nm at 12 dBm in power is injected into the setup to generate Stokes lines via the Stimulated Brillouin Scattering (SBS) process. The S-band BRFL is able of generating a Brillouin comb with 32 Stokes lines with a flat peak output power of − 18 dBm. The best BP to Stokes power ratio of the system is determined to be 50:50, while a ratio of 70:30 is observed to generate Stokes with a higher peak power, but at the expense of the number of wavelengths. The S-band BRFL has many potential applications as multiwavelength sources for communications and sensors. 相似文献
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The effect of output coupler reflectivity (or output coupling ratio) on the performance of a linear cavity Brillouin/erbium
fiber laser (BEFL) is demonstrated. The operating wavelength, output laser power and number of channels vary with changes
in the coupling ratio in the linear cavity system. The optimum BEFL operation is obtained with an output coupling of 40%,
i.e., 60% of the laser power is allowed to oscillate in the cavity. A stable laser comb consisting of up to 40 channels with
line spacings of approximately 0.09 nm are obtained at the Brillouin pump and 980 nm pump with powers of 2.5 mW and 100 mW,
respectively. The linear cavity BEFL has the potential to be used in inexpensive wavelength division multiplexing system.
相似文献