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Double Barrier Resonant Tunneling in Spin-Orbit Coupled Bose–Einstein Condensates

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Chinese Physics Letters 2013年第1期30卷 5-8页

作者： li Zhi WANG Jian-Zhong fu li-bin School of Physics Beijing Institute of TechnologyBeijing 100081 National Laboratory of Science and Technology on Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088 Center for Applied Physics and Technology Peking UniversityBeijing 100084

We study the double barrier tunneling properties of Dirac particles in spin-orbit coupled Bose–Einstein *** analytic expression of the transmission coefficient of Dirac particles penetrating into a double barrier is *** interesting resonance tunneling phenomenon is discovered in the Klein block region which has been ignored before.

关键词： Einstein tunneling Bose

Hydrogen Concentration Dependence of Bragg Wavelength of UV-Written Fiber Grating

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Chinese Physics Letters 1998年第12期15卷 886-888页

作者： fu li-bin TAN Gu XU Wan-jin liN Xiang-zhi liU Hong-du Department of Physics Peking UniversityBeijing 100871

Hydrogen loading provides highly enhanced photosensitivity in Ge-doped fiber. But the Bragg wavelength of UV-written fiber grating will shift from its initial value as the remaining hydrogen diffuses out of such fiber. A simple model to calculate the index change of hydrogenated fibers is presented. The theoretical model is in good agreement with experimental results and it can well predict the final wavelength position of UV-written weak fiber grating.

关键词： fiber fibers value

Compact Single-Mode Distributed Bragg Reflector Fiber Laser

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Chinese Physics Letters 2000年第2期17卷 109-111页

作者： XUE Yi-Yuan AN Hong-lin fu li-bin liN Xiang-Zhi liU Hong-Du Department of Physics Peking UniversityBeijing 100871

A compact single-mode distributed Bragg reflector (DBR) fiber laser with narrow spectral linewidth is investigated. Firstly, based on our theoretical analysis the single longitudinal mode operation domain is obtained. Then, a single-mode DBR fiber laser of 7.9cm long with master oscillator power amplifier (MOPA) configuration is designed and constructed to operate in the single-mode domain. The fiber laser is pumped by a semiconductor laser at 975.5nm. The master oscillator operates at 1556.91 nm with a cw output power of 1.43mW for a pump power of 55.35 mW. Its slope efficiency is 2.7% and the spectral linewidth is less than 1.2MHz (instrument resolution limited). With the MOPA configuration the laser output power and slope efficiency are increased to 7.8mW and 16.9%, respectively.

关键词： fiber amplifier pumped

Electrically Tunable Optical Fiber Mach- Zehnder Interferometer

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Chinese Physics Letters 1999年第7期16卷 516-517页

作者： XING Jie fu li-bin XU Wan-jing liN Xiang-zhi liU Hong-du li Yi-jun SHAO Yan-bin HU Dan-ping CHEN Yan-chuan Department of Physics Peking UniversityBeijing 100871 North China Research Institute of Electron-Optics Beijing 100015

An electrically tunable optical fibre Macli-Zehnder interferometer is reported,based on the magnetostrictive *** period and peak wavelength of the interference spectrum can be electrically tuned to match the International Telecommunication Union standard wavelength grid and so it is promising to be used in dense wavelength division multiplexing technology.

关键词： interferometer tunable effect.

New Method to Obtain Strain Gradient Chirped Fiber Bragg Gratings

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Chinese Physics Letters 1999年第12期16卷 902-904页

作者： WANG ling fu li-bin XU Wan-jin AN Hong-lin liN Xiang-zhi liU Hong-du Department of Physics Peking UniversityBeijing 100871

We describe a new method for applying a strain gradient with different profiles to convert uniform fiber Bragg gratings into linear or non-linear chirped ones. The chirping profile and the chirp rate of the fiber gratings can be controlled by simply varying the tension applied. Both the theory and experimental results are presented.

关键词： fiber chirp convert

Photosensitivity and Hydroxyl in Hydrogenated Silica Fibers

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Chinese Physics Letters 1998年第9期15卷 657-658页

作者： TAN Gu liN Xiang-zhi liU Hong-du fu li-bin E.Y.B.Pun P.S.Chung Department of Physics Peking UniversityBeijing 100871 Department of Electronical Engineering City University of Hong Kong

Optical loss spectra and refractive index changes have been measured in the hydrogenated standard telecommu-nication fiber and photosensitive *** index changes due to ultraviolet exposure were found to be closely related with the OH formation in both types of fibers.A direct photolyticd model is proposed to explain the effect of hydrogen loading on the enhancement of the photosensitivity in silica fibers.

关键词： loading ultraviolet effect

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非线性三能级体系的绝热朗道-齐纳隧穿

物理学报 2007年第7期56卷 3733-3738页

作者：王冠芳刘彬傅立斌赵鸿北京应用物理与计算数学研究所北京100088 兰州大学物理科学与技术学院理论物理研究所

研究了绝热条件下非线性三能级体系的朗道-齐纳隧穿.通过研究体系的本征值和本征态,发现当非线性不是很强时,三个能级的结构与线性情况相似,但中间能级所对应本征态的性质分段,这种分段导致绝热定理被破坏,引起所谓的绝热隧穿现象.由于... 详细信息

研究了绝热条件下非线性三能级体系的朗道-齐纳隧穿.通过研究体系的本征值和本征态,发现当非线性不是很强时,三个能级的结构与线性情况相似,但中间能级所对应本征态的性质分段,这种分段导致绝热定理被破坏,引起所谓的绝热隧穿现象.由于本征态的不稳定性,造成隧穿率的混乱.当非线性较强时,能级结构发生非常复杂的扭曲,使绝热定理被更加严重地破坏.还讨论了这个模型在三势阱波色-爱因斯坦凝聚体系中的可能应用.

关键词：三能级朗道齐纳隧穿隧穿率

Short- and long-term outcomes of lung volume reduction surgery

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Chinese Medical Journal 2006年第9期119卷 769-773页

作者： li Tong HOU Sheng-cai li Hui HU bin MIAO Jin-bai ZHANG Zhen-kui WANG Yang fu Yi-li YOU bin Department of Thoracic Surgery Beijing Chaoyang Hospital Capital University of Medical Sciences Beijing 100020 China

In 1957, Brantigan applied lung volume reduction surgery （LVRS） to the treatment of emphysema. In 1995, Cooper reused this operation and obtained remarkable benefit in patients with chronic obstructive pulmonary disease （COPD）. Although there are still some doubts about the effect of LVRS, in the past 10 years, a lot of clinical information approved that LVRS can give benefit to more than 70% of COPD patients. At present, a series of researches in long-term investigation and function evaluation such as NETT have got elementary affirmative conclusion about some disputative problems.

关键词： chronic obstructive pulmonary disease lung volume reduction surgery early-term result long-term result

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“广东音乐”旋法特征探究

黄钟（武汉音乐学院学报） 2007年第3期 58-63页

作者：李复斌广州星海音乐学院民乐系

广东音乐以句首弱起、装饰音(帽头花)、音型与节奏的重复、音阶进行和模进为主要特征的创作手法。源于粤剧过场音乐和唱腔的广东音乐因时代的不同、社会背景的不同和社会需求的不同,曾吸收和融合了江南丝竹的元素和思维,并借鉴了西洋音... 详细信息

广东音乐以句首弱起、装饰音(帽头花)、音型与节奏的重复、音阶进行和模进为主要特征的创作手法。源于粤剧过场音乐和唱腔的广东音乐因时代的不同、社会背景的不同和社会需求的不同,曾吸收和融合了江南丝竹的元素和思维,并借鉴了西洋音乐中的音调与技法,使之成为一种风格独特的地方乐种。

关键词：广东音乐旋法特征句首弱起装饰音江南丝竹