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Characteristics of perfluorinated amine media for stimulated brillouin scattering in hundreds of picoseconds pulse compression at 532 nm

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Chinese Optics Letters 2015年第6期13卷 73-77页

作者：哈斯乌力吉赵航林殿阳伟明吕志伟 National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of Technology

The characteristics of stimulated brillouin scattering （SBS） in perfluorinated amine media and the experimental structure used in hundreds of picoseconds pulse compression at 532 nm are demonstrated. A two-stage SBS pulse compression structure is adopted for this work. The compact double-cell SBS compression structure and the scattering media FC-70 are chosen to compress the incident light from 9.5 to about 1 ns in the first stage. Then, the light is used as the pumping source for the second pulse compression. In the second stage, using a single-cell SBS structure in a pulse compression system, perfluorinated amine media with different phonon lifetimes, such as FC-3283, FC-40, FC-43, and FC-70, are chosen to run the comparative experimental study. The narrowest com- pressed pulse times obtained are 294, 274, 277, and 194 ps; they respectively correspond to the above listed media. The average width of the compressed pulse width is 320 ps for FC-3283, with a fluctuation range of 87 ps. For FC-40, the average pulse width is 320 ps, with a fluctuation range of 72 ps. And for FC-43, the average pulse width is 335 ps, with a fluctuation range of 88 ps. However, the average pulse width is only 280 ps for FC- 70, with a fluctuation range of 57 ps. The highest energy reflectivity is more than 80% for all of the media. The experimental results show that a two-stage SBS pulse compression system has lower pump energy requirements, thus making it easier to achieve a compressed pulse waveform. The results also show that the shorter the phonon lifetime of the medium, the narrower the obtained compressed pulse width.

关键词： brillouin scattering Phonons Pulse compression Stimulated brillouin scattering

Research on stimulated brillouin scattering suppression based on multi-frequency phase modulation

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Chinese Optics Letters 2009年第1期7卷 29-31页

作者：刘英繁吕志伟董永康李强 Institute of Opto-Electronics Harbin Institute of Technology

The method of generating equal-amplitude spectral lines by multi-frequency phase modulation is used in stimulated brillouin scattering （SBS） suppression. The spectra of three, five, seven, and eleven equalamplitude spectral lines are obtained in experiment with flatnesses less than 0.3 dB. Theoretical research on SBS suppression shows that the threshold power after modulation is in reverse proportion to the maximum square of amplitude moduli of fundamental frequency and the nth harmonic wave. The threshold powers of three, five, seven, and eleven equal-amplitude spectral lines are improved by 5.21, 8.36, 9.39, and 10.76 dB, respectively.

关键词： brillouin scattering Frequency domain analysis Light polarization Phase modulation Polarization Spectrum analysis Stimulated brillouin scattering Ultrasonics

Stimulated brillouin scattering phase conjugation of light beams carrying orbit angular momentum(Invited Paper)

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Chinese Optics Letters 2017年第3期15卷 21-23页

作者：陈旭东昌成成蒲继雄 Fujian Key Laboratory of Light Propagation and Transformation College of Information Science and Engineering Huaqiao University Xiamen 361021 China

We investigate the stimulated brillouin scattering （SBS） properties of light beams carrying orbit angular momentum （OAM）. The phase conjugation of light beams carrying OAM is experimentally achieved in an SBS mirror with a random phase plate. The spectrum and the pulse width compression of SBS light are measured. It is shown that the phenomena of pulse compression is observed and OAM conservation is confirmed in the SBS process. The OAM transfer from photons to phonons may find potential applications in photon-phonon conversion-based signal-processing schemes by using OAM multiplexing.

关键词： Angular momentum brillouin scattering Light Phonons Photons Signal processing Solid state lasers

Generation of high-energy 284 ps laser pulse without tail modulation by stimulated brillouin scattering

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Chinese Optics Letters 2016年第9期14卷 67-70页

作者：刘照虹王雨雷王一锐远航白振旭王红丽刘瑞李森森张恒康周罗贤谭谈何伟明吕志伟 National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of Technology

We obtain the output of a 284 ps pulse duration without tail modulation based on stimulated brillouin scattering（SBS） pulse compression pumped by an 8 ns-pulse-duration, 1064 nm-wavelength Q-switched Nd：YAG laser. To suppress the tail modulation in SBS pulse compression, proper attenuators, which can control the pump energy within a rational range, are added in a generator-amplifier setup. The experimental result shows that the effective energy conversion efficiency triples when the pump energy reaches 700 m J to 51%, compared with the conventional generator-amplifier setup.

关键词： brillouin scattering Conversion efficiency Energy conversion Modulation Neodymium lasers Optical pumping Pulse compression Pumping (laser) Ultrashort pulses

Stimulated brillouin scattering threshold dependent on temporal characteristics in a kilowatt-peak-power,single-frequency nanosecond pulsed fiber amplifier

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Chinese Optics Letters 2016年第3期14卷 59-63页

作者：胡曼全昭王建华刘恺陈晓龙赵纯漆云凤何兵周军 Shanghai Key Laboratory of All Solid-State Laser and Applied Techniques Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Department of Space and Command Academy of EquipmentBeijing 101416China

The stimulated brillouin scattering （SBS） threshold affected by repetition rate and pulse duration in a single- frequency nanosecond pulsed fiber amplifier is studied. The experimental results demonstrate that the SBS threshold can be improved either by reducing the repetition rate or by narrowing the pulse duration; however, the average power may be limited in some cases. Otherwise, two evaluation methods for the SBS threshold in the fiber amplifier are compared and discussed, aiming to obtain a more accurate description for the SBS threshold in our single-frequency amplifier system.

关键词： brillouin scattering Fiber amplifiers Pulse amplifiers Pulse repetition rate

Influence of medium parameters on power limiting characteristic in stimulated brillouin scattering process

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Chinese Optics Letters 2007年第11期5卷 674-676页

作者：龚华平吕志伟林殿阳刘松江 Institute of Opto-Electronics Harbin Institute of Technology Harbin 150001 Institute of Opto-ElectronicsChina Jiliang UniversityHangzhou 310018 Institute of Opto-Electronics Harbin Institute of Technology Harbin 150001 Institute of Opto-Electronics Harbin Institute of Technology Harbin 150001 Department of PhysicsDaqing Petroleum InstituteDaqing 163318

By adopting noise initiation model of stimulated brillouin scattering （SBS）, the influence of phonon lifetime and gain coefficient of medium on power limiting characteristic is numerically investigated. Through using actual parameters of three media, CCl4, acetone, and CS2, the waveforms of transmitted pulses are simulated. The result shows that different media have little effect on the front peak of waveform, while have an obvious effect on the height of power limiting platform. When the medium which has short phonon lifetime and small gain coefficient is used, the height of power limiting platform is comparatively high. In experiment, by focusing 1064-nm, 8-ns, 18-mJ pulses into these three media, the waveforms of transmitted pulses are obtained. The experimental results are in good agreement with conclusions of theoretical simulations.

关键词： brillouin scattering High power lasers Nonlinear effects Optical limiting Stimulated brillouin scattering Stimulated scattering

Determination of elastic,piezoelectric,and dielectric constants of an R:BaTiO_3 single crystal by brillouin scattering

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Chinese Physics B 2012年第6期21卷 510-514页

作者：何小亢曾立波吴琼水张丽艳朱恪刘玉龙 Electronic Information School Wuhan University Institute of Physics Chinese Academy of Sciences

From the sound velocity measured using the brillouin scattering technique, the elastic, piezoelectric, and dielectric constants of a high-quality monodomain tetragonal Rh：BaTiO3 single crystal are determined at room temperature. The elastic constants are in fairly good agreement with those of the BaTiO3 single crystal, measured previously by brillouin scattering and the low-frequency equivalent circuit methods. However, their electromeehanical properties are significantly different. Based on the sound propagation equations and these results, the directional dependence of the compressional modulus and the shear modulus of Rh：BaTiO3 in the （010） plane is investigated. Some properties of sound propagation and electromechanical coupling in the crystal are discussed.

关键词： brillouin scattering elastic and piezoelectric constants Rh:BaTiO3 single crystal

High‐sensitivity distributed dynamic strain sensing by combining Rayleigh and brillouin scattering

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Opto-Electronic Advances 2020年第12期3卷 1-8页

作者： Benzhang Wang Dexin Ba Qi Chu Liqiang Qiu Dengwang Zhou Yongkang Dong National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150001China

The phase-sensitive optical time-domain reflectometry(φ-OTDR)is a good candidate for distributed dynamic strain sensing,due to its high sensitivity and fast measurement,which has already been widely used in intrusion monitoring,geophysical exploration,*** the frequency scanning basedφ-OTDR,the phase change manifests itself as a shift of the intensity *** correlation between the reference and measured spectra is employed for relative strain demodulation,which has imposed the continuous measurement for the absolute strain ***,the brillouin optical time domain analysis(BOTDA)allows for the absolute strain demodulation with only one *** this work,the combination of theφ-OTDR and BOTDA has been proposed and demonstrated by using the same set of frequency-scanning optical pulses,and the frequency-agile technique is also introduced for fast measurements.A 9.9 Hz vibration with a strain range of 500 nεhas been measured under two different absolute strains(296.7μεand 554.8με)by integrating the Rayleigh and brillouin *** sub-micro strain vibration is demonstrated by theφ-OTDR signal with a high sensitivity of 6.8 nε,while the absolute strain is measured by the BOTDA signal with an accuracy of 5.4με.The proposed sensor allows for dynamic absolute strain measurements with a high sensitivity,thus opening a door for new possibilities which are yet to be explored.

关键词： fiber optics sensor Rayleigh scattering brillouin scattering fast measurement

Study on forward stimulated brillouin scattering in a backward pumped fiber Raman amplifier

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Chinese Optics Letters 2004年第11期2卷 627-629页

作者：张在宣李来晓耿丹戴碧智金永兴刘红林 Insoo S.Kim 王剑锋吴孝彪方达伟庄松林 Optelectronics Technology Institute College of Optics and Electronics Information & Optical Technology Research Group

Strong multi-order forward stimulated brillouin scattering (SBS) has been observed in the backward pumped S-band distributed fiber Raman amplifier (PRA) with tunable narrow signal source (less than 100 MHz) when the pump power of FRA reached the SBS threshold. This does not obey the theory that only weak backward SBS lines exist according to the conservation of energy and momentum and the wave vector selected rule. This is because the sound waveguide characteristic weakens the wave vector rule, and the forward transmitted sound waveguide brillouin scattering lines are generated and amplified in FRA. When the pump power is further increased, 11 orders of SBS lines and comb-like profile are observed. For the excited line, the frequency is 197.2296 THz and the power is 0 dBm. The even order SBS lines are stronger than odd order SBS lines, the power of the 2nd and 4th order SBS lines is 1.75 dBm, which is 16 dB higher than that of the 1st and 3rd order SBS lines. The odd order SBS lines are named brillouin Rayleigh scattering lines.

关键词： brillouin scattering Optical communication Optical pumping Raman scattering Stimulated emission