Effects of electron temperature on dielectric function and localization of laser beams in underdense collisional plasma

Effects of electron temperature on dielectric function and localization of laser beams in underdense collisional plasmas are investigated. Simulation results show that the electron temperature has a strong effect on the dielectric constant and the laser beam localization. It is observed that due to the influence of the electron temperature, the dielectric function presents some interesting and complicated nonlinear variations, and gives rise to the laser beam localization. Moreover, the amplitudes of the beam width and the beam intensity are subjected to continuously oscillatory variation in the region of localization. In addition, the effects of several parameters on the dielectric function and the beam localization are discussed.     

Dynamics of Analytical Matter-Wave Solutions in Three-Dimensional Bose–Einstein Condensates with Two- and Three-Body Interactions

Using the F-expansion method we present analytical matter-wave solutions to Bose-Einstein condensates with two- and three-body interactions through the generalized three-dimensional Gross-Pitaevskii equation with time- dependent coefficients, for the periodically time-varying interactions and quadratic potential strength. Such solutions exist under certain conditions, and impose constraints on the functions describing potential strength, nonlinearities, and gain （loss）. Various shapes of analytical matter-wave solutions which have important applications of physical interest are s~udied in details.     

驻波演示仪的制作

每当讲到波动学的"驻波"这一节时,老师感觉难讲,学生也感觉难学.对于驻波在质点振动,相位变化,波形及能量的传播等方面与行波的区别,学生总爱犯糊涂.如果能结合教学演示仪,边讲边演示.学生对驻波这一特殊的波动形式就容易理解了.     

驻波演示仪的制作

本文分析介绍了横驻波演示仪和纵驻波演示仪的制作方法及其演示步骤。