排序方式: 共有10条查询结果,搜索用时 15 毫秒
1
1.
N. S. Kazak E. G. Katranji I. A. Utkin A. A. Ryzhevich A. N. Khilo 《Journal of Applied Spectroscopy》2004,71(5):697-701
The phenomenon of self-diffraction of Bessel light beams (BLB) in a nonlinear liquid medium has been studied experimentally and theoretically for the first time. Diffraction maxima which do not correspond to integer orders for an induced periodic structure have been registered. It has been shown that the appearance of these maxima is due to the initial BLB modulation, which can be caused by the departure of the axicon refracting surface from the ideal conical surface, as well as by the imperfection of the form of the Gaussian beam incident on the axicon. 相似文献
2.
本文推导了包含自衍射及非线性吸收影响、用以描述空间电荷场建立过程的微分方程组,阐明了周期性的空间电荷场与光强干涉条纹之间的相位差在建立过程中所起的作用,并推导了描述条纹倾斜和弯曲的微分方程。通过数值计算找到了硅酸铋(BSO)晶体中能量转移的规律,讨论了材料特性对过程快慢的影响,提出了用CW激光来探讨瞬态过程快慢的可能性。 相似文献
3.
On the basis of the modified Bloch equations a theory is developed of the light self-diffraction in a thin film of a dense resonant medium with allowance for the dipole-dipole interactions of atoms. It is shown that for certain values of intensity of an external field, there occurs in the film the light-induced first-kind phase transition which causes the emergence of regions (domains) with the high excitation of atoms. The switching effects of the system dense resonant medium + periodically-modulated field under consideration result in a hysteresis behaviour in the dependence of the diffraction efficiency on the adiabatically changing intensity of the external field. The predicted hysteresis offers additional potentialities in the investigation of the dynamics of the first-kind phase transition in dense media and outlook for usage of the film as a switching logical element. 相似文献
4.
5.
J. Vanhanen S. Parkkinen V. P. Leppanen T. Jaaskelainen J. P. S. Parkkinen 《Optical Review》2001,8(5):368-372
Holographic properties of a 13-demethyl retinal bacteriorhodopsin (13-demethyl BR) film in gelatin matrix were investigated and compared to those of a native bacteriorhodopsin (BRWT) film. A two-wave mixing experiment was performed to study the self-diffraction efficiency of the samples. The rise and the decay of the grating in the 13-demethyl BR film was measured. The film is relatively slow enabling the recording of simultaneous gratings. Phase conjugate reflectivity was measured by a four-wave mixing experiment. Diffraction efficiency and phase conjugate reflectivity of the 13-demethyl BR film were observed to be comparable to those of the BRWT film. 相似文献
6.
利用激光感应瞬态光栅技术测量超短激光脉冲宽度 总被引:1,自引:0,他引:1
描述了利用激光感应瞬态光栅技术测量超短脉冲激光的脉冲宽度和相干时间的方法,来自同一光源的两束激光在非线性介质中相干形成积分光栅,测量光栅自衍射强度与两束光脉冲之间的延迟时间关系,利用相干光束的四阶相干函数关系,可以求出光源的脉冲宽度和相干时间。 相似文献
7.
8.
自衍射效应在飞秒激光领域有非常重要的应用,如提高飞秒脉冲的时域对比度、作为自参考光谱干涉脉冲测量法的参考光、作为频率分辨光学开关法的信号光等.然而,具有较宽光谱带宽的飞秒激光在自衍射效应过程中产生的信号光存在明显的角色散,这给自衍射效应的应用带来不利影响.本文研究发现通过在自衍射效应的一个光路中加入等腰直角棱镜,当到棱镜的入射角为23fi时可以明显地减小飞秒激光脉冲自衍射信号的角色散.这就为以后将自衍射效应更好的应用到飞秒激光脉冲的研究提供了有用的参考. 相似文献
9.
报道了激光诱导热效应光栅自衍射效率与两入射激光束夹角的依赖关系,实验结果给出自衍射效率与夹角的四次方成反比,理论分析与实验结果一致。 相似文献
10.
克尔介质中光波的自衍射效率的理论计算 总被引:1,自引:0,他引:1
采用前向四波耦合的理论模型研究了薄克尔介质的厚度,吸收,入射光强等因素对光波自射效率的影响,详细分析了光波的位相变化,位相失配以及二波混频项的作用。 相似文献
1