检索结果-南通市图书馆

Theoretical modelling of the effect of photon lifetime on the output dynamics of Er-doped distributed feedback fibre lasers

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2008年第1期17卷 217-223页

作者：王利陈柏陈嘉琳常丽萍李国扬孙安林尊琪 shanghai institute of optics and Fine mechanics Chinese Academy of Sciences

By employing a simple model of describing three-level lasers, we have theoretically investigated the effect of photon lifetime on the output dynamics of Er-doped distributed feedback fibre lasers. And based on the the... 详细信息

关键词： photon lifetime self-pulsing Er-doped fibre distributed feedback laser

Real-time measurement of the fast axis angle of a quarter-wave plate based on simultaneous phase shifting technique

在线全文

学校读者我要写书评

暂无评论

Chinese optics Letters 2008年第8期6卷 568-571页

作者：杨坤曾爱军王向朝王华唐锋 shanghai institute of optics and Fine mechanics Chinese Academy of Sciences shanghai Hengyi optics and Fine mechanics Co. Ltd.

Real-time measurement of the fast axis angle of a quarter-wave plate based on simultaneous phase shifting technique is presented. The simultaneous phase shifting function is realized by an orthogonal grating, a diaphragm, an analyzer array, and a 4-quadrant detector. The intensities of the light beams from the four analyzers with different azimuths are measured simultaneously. The fast axis angle of the quarter-wave plate is obtained through the four light intensity values. In this method, rotating elements are not required, so real-time measurement is achieved.

关键词： Electromagnetic waves

Sinusoidal phase-modulating laser diode interferometer for real-time surface profile measurement

在线全文

学校读者我要写书评

暂无评论

Chinese optics Letters 2007年第3期5卷 164-167页

作者：何国田王向朝曾爱军唐锋 shanghai institute of optics and Fine mechanics Chinese Academy of Sciences shanghai Hengyi optics & Fine mechanics Co. Ltd.

A sinusoidal phase-modulating （SPM） laser diode （LD） interferometer for real-time surface profile measurement is proposed and its principle is analyzed. The phase signal of the surface profile is detected from the sinusoidal phase-modulating interference signal using a real-time phase detection circuit. For 60 × 60 measurement points of the surface profile, the measuring time is 10 ms. A root mean square （RMS） measurement repeatability of 3.93 nm is realized, and the measurement resolution reaches 0.19 nm.

关键词： Interferometers Phase modulation Real time systems Semiconductor lasers Signal detection

Real-time displacement measurement with large range and high accuracy using sinusoidal phase modulating laser diode interferometer

在线全文

学校读者我要写书评

暂无评论

Chinese optics Letters 2007年第4期5卷 211-214页

作者：何国田王向朝曾爱军唐锋黄炳杰 shanghai institute of optics and Fine mechanics Chinese Academy of Sciences shanghai Hengyi optics & Fine mechanics Co. Ltd.

To resolve the conflict of large measurement range and high accuracy in the existing real-time displacement measurement laser diode （LD） interferometers, a novel real-time displacement measurement LD interferometry is proposed and its measurement principle is analyzed. By use of a new phase demodulation algorithm and a new phase compensation algorithm of real-time phase unwrapping, the measurement accuracy is improved, and the measurement range is enlarged to a few wavelengths. In experiments, the peak-to-peak amplitude of the speaker vibration was 2361.7 nm, and the repeatability was 2.56 nm. The measurement time was less than 26 us.

关键词： Algorithms Interferometers Semiconductor lasers

Proposal of A New Space Atomic Frequency Standard

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1999年第7期16卷 478-480页

作者： WANG Xin-qi WANG Yu-zhu Laboratory for Quantum optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of ScienceShanghai 201800

A new prototype atomic fountain clock working in the micro-gravity environment is *** successive Ramsey interactions of cold atoms and oscillatory field are realized by means of comp u ter-con trolled periodic motion of oscillatory field while the cold atoms stay still relatively in the *** analyses in comparison with the atomic fountain clock working on the ground show that higher stability is obtainable in the prototype.

关键词： oscillatory successive stability

Radio-Frequency Field-Induced Quantum Interference Effects in Cold Atoms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2001年第11期18卷 1470-1472页

作者： LONG Quan ZHOU Shu-Yu ZHOU ShamYu WANG Yu-Zhu Laboratory for Quantum optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

We propose constructing a quantum interference configuration for cold atoms in a magneto-optical trap by applying a radio frequency field, which coherently couples adjacent Zeeman sublevels, in combination with a repumping laser field. One effect of this interference is that a dip exists in the absorption of the repumping light when the radio frequency is scanned. Our prediction has been indirectly detected through the fluorescence of cold atoms in a preliminary experiment.

关键词： pumping Quantum prediction

Photoionization Time-of-Flight Mass Spectra of Aluminum Clusters-Associated Complexes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1997年第9期14卷 663-666页

作者： NI Guo-quan ZHOU Ru-fang ZHAI Hua-jin WANG Yu-zhu Laboratory for Quantum optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Using a laser vaporization/pulsed molecular beam source,photoionization time-of-flight mass spectra of bare aluminum clusters Aln(n up to larger than 70)and of carbon-,oxygen-,and hydrogen-adducted aluminum clusters-associated complexes are *** cause of the observed odd-even alternation in reactivity of Aln and the formation mechanism of the informative products are discussed.

关键词： reactivity mechanism clusters

Direct Laser Writing Facility for Fabrication of Submicron Mask

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第4期31卷 185-188页

作者： ZHU Feng MA Jian-Yong Information optics Laboratory Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

Direct laser writing technique has become a well-established, multi-functional and flexible method for fabricating high quality diffractive optical elements. We propose and build a maskless direct laser writing system with the ability to produce a sub-micron feature size. The high precision lithography is realized by using the astigmatic autofocus method. The minimum feature size of the system, breaking through the diffraction limit with the chromium layer, can achieve 300hm with the 405nm blue laser. A 50 x 50ram2 chromium grating mask with a period of 1 #m and line width of 300 nm is fabricated. This facility will be useful for the fabrication of large-scale submicron diffraction optical elements in the future.

关键词： FABRICATION (Manufacturing) DIFFRACTIVE optical elements CHROMIUM -- Spectra BLUE lasers OPTICAL diffraction ASTIGMATISM (optics)

Anomalous Behaviour of Photorefractive Grating Erasure Owing to Existence of both Negative and Positive Carriers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2006年第6期23卷 1462-1465页

作者：朱荣刘德安郭袁俊柴志方刘立人 Information optics Laboratory Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

In LiNbO3：Fe, anomalous behaviour of grating erasure is observed with different wavelengths, i.e. rapid grating erasure in the short wavelength range, which deviates from the results predicted by the electron transport band model. The deviation is related to the coexistence of electrons and holes in photorefraction, and charge-transfer process including electrons and hole has been proposed. The electron and hole contributions to photoconductivity have been identified by experiments. We also give the theoretical dependence of electron photo-excitation coefficient S of the Fe centre on the wavelength.

关键词： INDUCED CHARGE-TRANSPORT HOLOGRAPHIC STORAGE CRYSTALS INTENSITIES ULTRAVIOLET LINBO3