共查询到20条相似文献,搜索用时 515 毫秒
1.
鉴于目前561 nm激光器噪声较大,影响其实用性,提出一种高稳定性低噪声的561 nm黄光激光器。利用Nd:YAG晶体得到1 123 nm基频光,通过LBO晶体腔内倍频得到561 nm输出。理论分析了1 112 nm、1 116 nm与1 123 nm波长的阈值泵浦功率,提出1 123 nm的单波长振荡条件,确定谐振腔镀膜要求。根据理论计算,设计了合理的谐振腔膜系,通过抑制1 112 nm与1 116 nm谱线在谐振腔内的振荡实现1 123 nm谱线的单波长振荡。在泵浦功率为5 W时,实现了561 nm激光单波长输出,输出功率达到107 mW,功率不稳定性达到0.7%,噪声为1.2%。 相似文献
2.
The power penalty and bit error rate degradation encountered when using wavelength division multiplexing devices is analyzed. Analysis is applied to the birefringent wavelength division multiplexer (BWDM) with a sinusoidal transfer function.1 The degradation in bit error rate is attributed to laser mode partition noise and crosstalk noise. 相似文献
3.
We demonstrated a fiber sensing system using the method of wavelength locking of two identical fibers Bragg gratings (FBG) to interrogate the wavelength shift by directly measuring the intensity of the reflection from the sensing Bragg grating. The light source of the fiber sensing system is an EDFA fiber ring laser pumped by a 980 nm laser diode and a narrow bandwidth fiber Bragg grating for the filter of the ring laser resonator. The wavelength shift is converted to the intensity deviation of the reflection from the sensing FBG under strain variation, and is able to achieve real-time sensing of the dynamic strain sensing in civil engineering. The characteristics and key factors to maintain stability of the dynamic strain sensing system are discussed. 相似文献
4.
The power penalty and bit error rate degradation encountered when using wavelength division multiplexing devices is analyzed. Analysis is applied to the birefringent wavelength division multiplexer (BWDM) with a sinusoidal transfer function.1 The degradation in bit error rate is attributed to laser mode partition noise and crosstalk noise. 相似文献
5.
A multimode linear cavity and a single-mode unidirectional ring cavity fiber laser with meter-long cavity lengths are shown to exhibit frequency noise limited by fundamental thermodynamic noise from 100?Hz to 100?kHz. Their measured spectra agree closely with theoretically derived thermodynamic noise and the characteristic dependence of the frequency noise power spectrum on the inverse of the cavity length is observed. The unidirectional ring laser exhibits a frequency noise of 2?Hz/Hz(1/2) at 1?kHz, one of the lowest published values to date from a free-running laser. The multimode linear cavity laser is shown to be a suitable candidate for thermal-noise-limited, meter-long fiber laser strain sensors with a strain resolution of 14?f?/Hz(1/2) at 1?kHz. 相似文献
6.
A tunable laser is demonstrated using a microfiber knot resonator structure made by erbiumdoped fiber (EDF). The laser is
made of a 2 m long EDF where 30 mm of its end section is tapered to construct a microfiber knot resonator (MKR). The combination
of the EDF and MKR generates a stable single wavelength laser at 1555 nm wavelength with a signal to noise ratio (SNR) of
33.7 dB using a 63 mW of 980 nm pump power. The peak wavelength of the laser can be tuned by 340 pm as the MKR diameter reduces
from 5.0 to 0.5 mm with an acceptable penalty in output power. 相似文献
7.
提出了一种kHz调制频率量级的单光子调制技术,实现对激光器的实时锁定. 通过探测乙炔气体的单光子吸收光谱,对离散的单光子响应脉冲进行锁定放大, 获得激光器频率锁定的鉴频曲线.将1.5 μm分布反馈半导体激光器的输出频率稳定在乙炔气体 ν1 + ν 3带P5e支吸收峰上,在175 s内典型激光频率起伏小于25 MHz. 这种基于单光子波长高频调制吸收光谱的稳频技术消除了低频段较高背景的噪声, 可应用于单光子量级的量子保密通讯系统以及光学波分复用系统. 相似文献
8.
在主动相位控制相干合成中,常用的光纤激光主动相位控制方法主要有外差法、多抖动法和随机并行梯度下降算法等. 基于多抖动法和外差法的原理,提出了一种新型的基于相位调制-解调的相位检测与控制方法. 该方法利用周期信号对参考光进行相位调制,将调制后的参考光与待检测信号光进行相干检测,通过对相干光强信号和相位调制信号的融合处理,实现相位噪声的检测和控制. 对该方法进行了数值模拟和实验研究. 实验结果表明,对于频率为2 kHz,噪声范围为[0,2π)的正弦噪声,相位检测精度优于λ/50,控制精度可达
关键词:
光纤激光
相干合成
相位噪声检测
调制-解调 相似文献
9.
Simulation-based comparison of noise effects in wavelength modulation spectroscopy and direct absorption TDLAS 总被引:1,自引:0,他引:1
B. Lins P. Zinn R. Engelbrecht B. Schmauss 《Applied physics. B, Lasers and optics》2010,100(2):367-376
A simulative investigation of noise effects in wavelength modulation spectroscopy (WMS) and direct absorption diode laser
absorption spectroscopy is presented. Special attention is paid to the impact of quantization noise of the analog-to-digital
conversion (ADC) of the photodetector signal in the two detection schemes with the goal of estimating the necessary ADC resolution
for each technique. With laser relative intensity noise (RIN), photodetector shot noise and thermal amplifier noise included,
the strategies used for noise reduction in direct and wavelength modulation spectroscopy are compared by simulating two respective
systems. Results show that because of the combined effects of dithering by RIN and signal averaging, the resolutions required
for the direct absorption setup are only slightly higher than for the WMS setup. Only for small contributions of RIN an increase
in resolution will significantly improve signal quality in the direct scheme. 相似文献
10.
1 Introduction Today ,theEr3 dopedfiberlaserandtheamplifierarewidelyusedinthefieldofopticalcommunicationandotherfields.TheYb3 dopedfiberlaserandamplifierhavebeeninventedandusedinmanyimportantfieldstoo ,andtheyareattractingmoreandmoreattention[1~ 4 ] .Compar… 相似文献
11.
Supercontinua generated by femtosecond pulses launched in microstructure fiber can exhibit significant low-frequency (<1-MHz) amplitude noise on the output pulse train. We show that this low-frequency noise is an amplified version of the amplitude noise that is already present on the input laser pulse train. Through both experimental measurements and numerical simulations, we quantify the noise amplification factor and its dependence on the supercontinuum wavelength and on the energy and duration of the input pulse. Interestingly, the dependence differs significantly from that of the broadband white-noise component, which arises from amplification of the input laser shot noise. 相似文献
12.
Xinhuan Feng Lei Sun Yange Liu Lingyun Xiong Shuzhong Yuan Guiyun Kai Xiaoyi Dong 《Optical and Quantum Electronics》2004,36(10):919-926
A simple actively mode-locked fiber ring laser is proposed and successfully demonstrated to generate dual-wavelength picosecond pulses with close wavelength spacing using one Bragg grating in standard single-mode fiber. The proposed laser can be made to operate in stable dual-wavelength at room temperature, due to the birefringence characteristic of the FBG induced by transverse strain. Transverse strain loading on the FBG allows the wavelength spacing to be controlled. Generation of stable dual-wavelength pulses with a pulsewidth of 212–234 ps and a tunable wavelength separation from 0.2 to 0.44 nm at a pulse rate of 1.05 GHz was demonstrated. 相似文献
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Nergis Mavalvala David E. McClelland Guido Mueller D. H. Reitze Roman Schnabel Benno Willke 《General Relativity and Gravitation》2011,43(2):569-592
Third generation terrestrial interferometric gravitational wave detectors will likely require significant advances in laser
and optical technologies to reduce two of the main limiting noise sources: thermal noise due to mirror coatings and quantum
noise arising from a combination of shot noise and radiation pressure noise. Increases in laser power and possible changes
of the operational wavelength require new high power laser sources and new electro-optic modulators and Faraday isolators.
Squeezed light can be used to further reduce the quantum noise while nano-structured optical components can be used to reduce
or eliminate mirror coating thermal noise as well as to implement all-reflective interferometer configurations to avoid thermal
effects in mirror substrates. This paper is intended to give an overview on the current state-of-the-art and future trends
in these areas of ongoing research and development. 相似文献
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17.
S.S. Chong H. Ahmad M.Z. Zulkifli A.A. Latif W.Y. Chong S.W. Harun 《Optics Communications》2012,285(6):1326-1330
A Dual-Wavelength Semiconductor Optical Amplifier (DW-SOA) based fiber ring laser with synchronous wavelength tunability is proposed and experimentally demonstrated. The SOA gain medium strongly suppresses mode competition, thus allowing stable dual-wavelength laser oscillation. The wavelength spacing of the two lasers can be tuned synchronously using a modified hybrid-tuning package incorporating a pair of Fiber Bragg Gratings (FBGs). The DW-SOA demonstrates a laser output with a wavelength spacing of between 0.10 and 8.30 nm (wavelength shift inequality of 0.08 to 0.75 nm). The relationship between the applied strain and wavelength shift of the two tuning modes is also analyzed. 相似文献
18.
Performance of gain-clamped erbium-doped fibre amplifier with different optical feedback schemes has been studied as a function of lasing wavelength. An inverse relation of the signal gains with the amplified spontaneous emission spectrum is observed for the entire laser tuning range as a result of the population variation caused by the different strength of the oscillating laser. The noise figure also shows a feature of the lasing wavelength dependence. However, co-feedback scheme exhibits behaviour opposite to that of the counter-feedback. 相似文献
19.
Tunable dual wavelength erbium-doped fiber laser (EDFL) with stable oscillation at room temperature is proposed and demonstrated. This laser utilizes a Bragg grating fabricated in a high birefringence fiber as the wavelength-selective component, and then achieves the stable dual wavelength oscillation by introducing the polarization hole burning effect. Furthermore, by applying lateral strain upon the fiber Bragg grating (FBG), the space of the laser dual wavelengths can be tuned continuously. 相似文献
20.
A laser-diode-pumped Nd:YVO4 orange solid-state laser is described in this paper. The fundamental wavelengths at 1064 and 1342 nm oscillate simultaneously and generate the 593.5 nm wavelength by intracavity sum-frequency mixing in a KTP crystal using type II phase matching. The noise characteristic of laser output has been measured and analyzed at different pumping powers. The relationship between the amplitude noise of sum-frequency mixing output and the longitudinal modes of fundamental frequency has been investigated. The results show that the sum-frequency mixing output has low noise if one of the fundamental wavelengths is single longitudinal mode. The experiment shows that amplitude noise of the intracavity sum-frequency mixing laser is lower than that of intracavity frequency doubled laser with the same structure. 相似文献