搜索结果: 151-165 共查到“知识库 激光物理”相关记录474条 . 查询时间(4.026 秒)
光学元件上不可避免存在的“缺陷”会对传输光束产生调制，基于广义惠更斯菲涅耳衍射积分和角谱的定义，推导出了高斯光束经有限个小尺寸振幅调制型“缺陷”之后的光强和角谱解析式。详细研究了振幅调制型“缺陷”的尺寸大小及调制幅度对受调制光束的光强分布和角谱影响。结果表明，经过“缺陷”的光束传输一定距离之后光强恢复为高斯分布。而“缺陷”的尺寸越大，光强分布恢复为高斯分布所需的传播距离越长，且随“缺陷”尺寸及调制...
Modifying molecule-surface scattering by ultrashort laser pulses
Modifying molecule-surface ultrashort laser pulses Quantum Physics
2011/8/2
Abstract: In recent years it became possible to align molecules in free space using ultrashort laser pulses. Here we explore two schemes for controlling molecule-surface scattering process, which are ...
基于量子理论方法的原子激光冷却机理分析
量子理论 原子冷却 冷却温度
2012/11/23
应用含保守系统和非保守系统的薛定谔方程分析了激光冷却机制，用该理论证明了原子在激光场中被冷却.并预言了原子冷却温度与原子振动频率成正比，该结论与最近在Nature发表的实验结果完全一致.
光学元件上不可避免地存在的“缺陷”会对传输光束产生局域振幅和相位调制。基于菲涅耳衍射积分，建立了高斯光束经局域相位调制后的传输模型，得到了高斯光束经有限多个小尺寸局域相位调制后的光强分布和角谱解析式，详细研究了相位调制尺寸与调制深度对光束光强分布和角谱的影响。结果表明，不同调制尺寸、调制深度对高斯光束在传输过程中的影响相似。且调制深度越大，产生的最大光强越大。相位“缺陷”尺寸越大产生的最大光强的位...
为了研究大气激光通信中稳定跟踪所采用的器件及有效跟踪方法,分析了光束定位探测器件(电荷耦合器件和四象限光电探测器)的灵敏度特性,结合影响大气激光通信跟踪系统性能的五种大气湍流效应,分别讨论了光束漂移、光强起伏、光斑弥散、到达角起伏及光束扩展的原理.对质心跟踪算法和形心跟踪算法定位准确度的影响进行分析,得到在大气条件下形心算法的跟踪误差小于质心误差的结论,并通过实验进行了验证.
溅射时间对脉冲激光沉积制备β-FeSi2薄膜的影响
脉冲激光沉积 ( PLD ) &beta -FeSi2薄膜 溅射时间
2012/3/26
本文基于脉冲激光沉积 (PLD)方法及热退火处理方式，利用输出波长为1064 nm的Nd:YAG脉冲激光器在P型Si (100) 衬底上生长了均匀的单相 β-FeSi2薄膜。采用X 射线衍射(XRD)、扫描电镜(SEM)、原子力显微镜(AFM)分析技术，研究了β-FeSi2薄膜的结构、组分、结晶质量和表面形貌。结果发现，在其他相同沉积条件下，随着溅射时间的增加，薄膜晶化程度、颗粒大小和形状、表面粗...
Emission characteristics of laser driven, dissipative coupled cavity systems
Emission characteristics laser driven dissipative coupled cavity systems
2010/11/22
We consider a laser driven and dissipative system of two coupled cavities with Jaynes-Cummings
nonlinearity. In particular, we investigate both incoherent and coherent laser driving, corresponding to...
Dynamic of rescattering-electron wave packets in strong and short-wavelength laser fields: Roles of Coulomb potential and excited states
scattering-electron wave packets in strong short-wavelength laser fields Coulomb potential excited states
2014/5/28
We investigate the high-order harmonic generation of atoms and molecules exposed in strong and shortwavelength (shorter than 800 nm) laser fields. Our simulations show that the electronic rescattering...
Demonstration of high-Q TE-TM photonic crystal nanobeam cavities
high-Q TE-TM photonic crystal nanobeam cavities Physics
2010/11/16
We experimentally demonstrate high Quality factor dual-polarized TE-TM photonic crystal nanobeam cavities. The free-standing nanobeams are fabricated in a 500 nm thick silicon layer, and are probed u...
Effects of Random Link Removal on the Photonic Band Gaps of Honeycomb Networks
the Photonic Band Gaps Honeycomb Networks
2010/11/16
We explore the effects of random link removal on the photonic band gaps of honeycomb networks. Missing or incomplete links are expected to be common in practical realizations of this class of connect...
We demonstrate a wideband-tunable Q-switched fiber laser exploiting a graphene saturable absorber.We get2μs pulses, tunable between 1522 and 1555nm with up to40nJ energy. This is a simple and low-co...
Tenfold enhancement of MeV Proton generation by a moderate ultra-short laser interaction with H2O nano-wire targets
MeV Proton generation moderate ultra-short laser H2O nano-wire targets
2010/11/12
Compact sources of high energy protons (50-500MeV) are expected to be key technology in a wide range of scientific applications. Particularly promising is the target normal sheath acceleration (TNSA) ...
A possibility of amplification of the 7.6 eV (3.5 eV) $\gamma$-radiation by the stimulated $\gamma$-emission of the ensemble of the $^{229m}$Th isomeric nuclei in a host dielectric crystal with a lar...
Photonic crystals are extremely sensitive to structural disorder even to the point of completely losing their functionalities. While on one side this can be detrimental for applications in traditiona...
Hadron electric polarizability -- finite volume corrections
Hadron electric polarizability finite corrections
2011/1/10
We use the background field method to extract the polarizability for the neutral “pion”. In our previous study we found that the polarizability for this system is negative which is believed to be a fi...