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101.
本文研究了在两个耦合的量子点和腔QED系统中的双模激子的压缩性质.讨论了不同的初始光场对双模激子的正常压缩与和压缩的影响.计算表明,当初始态光场制备在相干态时,双模激子既不存在正常压缩,也不存在和压缩,这说明双模激子振辐的两个正交分量具有相同的量子涨落;然而,当初始腔场处于压缩真空态时,无论是正常压缩还是和压缩,双模激子振辐的两个正交分量总有一个存在压缩.这意味着量子噪声能被有效的得到抑制.此外,两种情形下的最大压缩都由初始腔场的压缩因子r决定.经过比较,我们还发现双模激子的正常压缩比和压缩大. 相似文献
102.
HE Meng LIU Guo-Zhen XIANG Wen-Feng Lü Hui-Bin JIN Kui-Juan ZHOU Yue-Liang YANG Guo-Zhen 《中国物理快报》2007,24(9):2671-2674
A series of amorphous and single-crystalline LaAlO3 (LAO) thin films are fabricated by laser molecular-beam epitaxy technique on Si substrates under various conditions of deposition. The structure stability of the LAO films annealed in high temperature and various ambients is studied by x-ray diffraction as well as high-resolution transmission electron microscopy. The results show that the epitaxial LAO films have very good stability, and the structures of amorphous LAO thin films depend strongly on the conditions of deposition and post-annealing. The results reveal that the formation of LAO composition during the deposition is very important for the structure stability of LAO thin films. 相似文献
103.
XIANG Shiqing LOU Qihong DONG Jingxing MANG Yanping WEI Yunrong 《Chinese Journal of Lasers》1996,5(5):385-390
Generationof2-10nsExcimerLaserPulsebyOpticalSynchronizingWave-clippingXIANGShiqing;LOUQihong;DONGJingxing;MANGYanping;WEIYunr... 相似文献
104.
CHEN RuiLin ZENG QingYuan HUANG YunQing XIANG Jun WEN Ying GUO XiaoGang YIN ChangJun DONG Hui & ZHAO Gang Hunan Key Laboratory for Computation Simulation in Science Engineering Xiangtan University Xiangtan China School of Civil Engineering & Mechanics School of Civil Architecture Central South University Changsha AMEC Toronto MAG Canada 《中国科学:物理学 力学 天文学(英文版)》2010,(4)
Based on the analysis theory of random energy of train derailment, an analysis theory of random energy of train derailment in wind is suggested. Two methods are proposed -the time domain method and the frequency domain method of analysis theory of random energy of train derailment in wind. The curves of σ pw -v under various wind speeds are obtained through the computation. The original curve of σ p -v is expanded, which turns the analysis theory of random energy of train derailment into the all-weather theory. Train derailment condition has been established under wind action. The first and second criterions of train derailment have been proposed in light of wind action. The analysis of train derailment cases at home or abroad is made, in- cluding the first analysis of Xinjiang train derailment case encountered 13-level of gale, which explained the inevitability of train derailment. The analysis theory of random energy of train derailment in wind shows its validity and accuracy. The input energy σ pw of the transverse vibration of train-track(bridge)-wind system is linked to train speed. With the establishment of the analysis theory of random energy of train derailment in wind, It is likely to initiate an all-weather speed limit map for a train or any high-speed train. 相似文献
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We investigate the entanglement dynamics of a quantum system consisting of three superconducting charge qubits (SCQs) interacting with a microwave field. For separable and entangled states of the SCQs, the evolutions are studied under various photon numbers of cavity field. The results show that the amplitude and period of the bipartite entanglement square concurrences can be controlled by the choice of initial states of SCQs and photon numberof cavity field, respectively. This simple model of a quantum register allows us to understand the dynamic process of the quantum storage of information carried by charge qubit. 相似文献
108.
We study the entanglement dynamics between two strongly-AC-driven superconducting charge qubits coupled collectively to a zero temperature, dissipative resonator and find an unusual feather that the competing of creation and annihilation of entanglement can lead to entanglement increasing, sudden death and revival. We also calculate the dependence of the death time on the initial state of the system. 相似文献
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基于单粒子导心运动代码ORBIT,采用测试粒子模拟方法,研究了托卡马克等离子体内部不同径向位置处局域磁场扰动对高能量离子的损失的影响。研究表明,在局域磁扰动主要分布在某磁面附近、其环向具有类似纹波场形式下,可造成一些靠近等离子体中心区域的高能量离子损失,但对靠近等离子边界的离子损失影响相对不大。这些损失的高能量离子均为捕获离子,离子的投掷角越大就越容易损失。此外,造成高能量离子最大损失率的局域场径向位置与这些损失离子的初始径向位置通常存在一定的偏移,而且这个偏移与这些离子的能量密切相关。当局域场出现在某些位置时,能量较低的离子会有一定的损失,能量较高的离子反而不会损失。 相似文献