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 共查询到19条相似文献,搜索用时 125 毫秒
1.
利用哈密顿形式的光线追迹方程对几种作用情况下相对论电离波前导致的探针波频率转换现象进行了理论上的研究。指出探针波频率不但会上移,条件合适时还会发生下移。反射角和透射角一般也会发生显著变化。  相似文献   

2.
屈卫星  余玮  徐至展 《物理学报》1997,46(4):666-671
对电磁波在强激光驱动的运动等离子体界面上的反射和透射进行了研究,根据电磁场在等离子体界面上所满足的边界条件以及电磁场的相对论变换理论,推导出了s偏振的电磁波在该运动等离子体界面上的反射和透射系数的表达式,并对几种特殊情况进行了讨论 关键词:  相似文献   

3.
本文就大学物理相对论中在不同参考系中测量事件的问题进行了讨论,希望在教学中进一步加强对相对论的理解.  相似文献   

4.
利用相对论质能关系、不同参考系中电磁场的变换关系和牛顿第二定律,先研究了一般的电源电动势在不同参考系之间的变换,再推导出相对论中的感生电动势和动生电动势公式,从而使它们达到了定量的统一.  相似文献   

5.
基于细致组态(DCA)方法和跃迁系列群 (UTA) 模型,采用全相对论处理并结合量子亏损理论,计算了金Au激光等离子体的M带5f-3d跃迁的透射谱, 给出了金等离子体在不同电子温度和电子密度的时空电离态特性,平均电离度,离子丰度和离子内各能级的布居数,并模拟出Au等离子体的M 带5f-3d跃迁的细致谱线,其计算结果可对激光等离子体透射谱的电子温度和电子密度进行精密诊断.  相似文献   

6.
爱因斯坦火车是狭义相对论中展示同时性的相对性的经典模型, 爱因斯坦利用该模型证明了“ 同时性 的相对性” . 在狭义相对论中, 空间和时间并不相互独立, 而是一个统一的四维时空整体, 不同惯性参考系之间的时 空坐标变换关系式与洛伦兹变换在数学表达式上是一致的, 通过分析爱因斯坦火车模型中光在不同惯性参考系内 到达车壁的时间, 利用简单的数学变换更加容易地得到了洛伦兹变换, 从而验证了洛伦兹变换在狭义相对论的核 心地位  相似文献   

7.
我们已介绍过狭义相对论;在那里爱因斯坦把牛顿的相对性原理推广到包括电磁现象,但还是指惯性系说的;各个参考系是相对做匀速运动的惯性参考系.对加速参考系又该如何呢?爱因斯坦在马赫思想的影响下提出:物理规律对所有参考系,不管是惯性系还是加速系,都应该是一样的.这个进一步推广了的相对性原理叫“广义相对性原理”.它是爱因斯坦广义相对论的一个基本原理.  相似文献   

8.
对双频激光干涉测角中反射镜组内两角锥镜的不对称性进行了分析,包括两反射角锥镜的制造工艺误差——两反射角锥镜的厚度偏差,以及安装偏差——两反射角锥镜前表面不平行度。推导出了由于该类误差带来的测角影响,建立了精确的角度测量模型。  相似文献   

9.
董建峰  李杰 《物理学报》2013,62(6):64102-064102
研究了光轴平行于界面的单轴各向异性手征介质平板对平面电磁波的反射和透射特性, 推导出了反射和透射系数(功率)公式; 按介电常数的正负分4种情形给出了反射和透射功率曲线; 讨论了手征参数对反射和透射特性的影响, 特别是给出了伪布儒斯特角与手征参数的变化关系曲线. 关键词: 单轴各向异性手征介质 手征参数 伪布儒斯特角 反射和透射  相似文献   

10.
狭义相对论中的“光速不变原理”,议论的人很不少,下面谈谈我们对这问题的几点粗浅看法: 一、定义匀速直线运动离不开 “光速不变”假设 在狭义相对论中,几乎一开始就与两个彼此相互作匀速直线运动的惯性参考系打交道.要断定一个参考系相对于另一个参考系是否在作匀速直线运动,如果不想直接依赖“光速不变”假设来测定的话,就得要在不同地点放上一系列的钟,才能测定.这些放在某参考系中不同地点的钟,必须是对准了的或至少它们的读数之差是明确知道的,才能依靠它们来判断对方参考系是否的确在相同的时间里,走过相等的路程.不止如此,还需要有…  相似文献   

11.
Frequency upshifting of electromagnetic radiation impinging on a relativistically moving ionization front is theoretically investigated. Unlike previous works in this field treating the case of normal incidence and qualitatively similar case of oblique incidence of a transverse electric polarized wave, oblique incidence of a transverse magnetic polarized wave on the front is considered. The peculiarities of the case under consideration are connected with the generation of Langmuir waves behind the front and Brewster's phenomenon. We present a complete analysis of the incident wave transformation including analysis of the frequencies and amplitudes of the waves excited ahead of and behind the front. Special emphasis is made on energy transformation in the case when a wave packet is incident on the front. In particular, we show that even for negligible angles of incidence, energy losses via transformation into Langmuir waves may be very high (up to ~60%). In general, generation of Langmuir waves may play a significant role in the plasma-based radiation sources with relativistic ionization fronts  相似文献   

12.
基于当前等离子体物理,本文初步讨论了低环径比托卡马克堆中等离子体的特征。在自洽的低环径比堆芯参数下,计算了α粒子约束和损失,以及不同环径比对它们的影响。  相似文献   

13.
The interaction of an electromagnetic wave packet with a superluminous ionization front is described here using the Hamiltonian theory of photon acceleration. We also describe the interaction with accelerated ionization fronts. The different qualitative photon trajectories are presented for both cases. The frequency up-shift is also derived. It is shown that a proper tailoring of the ionization front velocity can lead to higher frequency up-shifts than in constant velocity ionization fronts  相似文献   

14.
The spectrum of coupled spin and electromagnetic waves is obtained for a magnetic with a ferromagnetic spiral structure determined by nonuniform exchange and relativistic interactions. It is shown that resonant interaction between spin and electromagnetic waves is possible. The electromagnetic wave reflectance from the plate of a magnetic with a ferromagnetic spiral is calculated for different spiral angles.  相似文献   

15.
利用了匀速运动的均匀等离子体中电磁场的色散关系,对电磁波与由强激光驱动的运动电离波面的相互作用过程中出现的静磁模进行了研究,发现在特定的条件下振荡电场也会在该过程中出现,并确定了振荡电场产生的条件 关键词:  相似文献   

16.
The interaction of a light wave with a relativistic ionization front in the presence of an applied DC magnetic field which is perpendicular or parallel to the incident wave is considered. In both cases, four transmitted modes are generated in the magnetized plasma by an incident linearly polarized wave. The frequency upshifts of the various modes are calculated and compared to the unmagnetized case. The corresponding reflection and transmission coefficients are also obtained. Finally, the density ripple associated with the free streaming mode in a magnetized plasma for the perpendicular case is discussed  相似文献   

17.
The propagation of a short intense laser pulse is studied in a gas taking into account the ionization of gas atoms by the high-frequency electromagnetic field of the pulse. The conditions are found under which the ionization structures produced by the laser pulse cause the pulse focusing accompanied by a substantial increase in its intensity. It is shown that the leading edge of the pulse is subjected to ionization refraction at the ionization front, the temporal profile of the pulse becoming steeper. This results in the efficient generation of a wake wave at the ionization front, which is amplified during the development of self-modulation instability. The amplitude of the wake plasma wave achieves a substantial value already at small paths of the pulse in matter (smaller than the diffraction length of the pulse).  相似文献   

18.
The ponderomotive force plays a fundamental role in the absorption of laser light on self-consistent plasma density profiles, in multiple-photon ionization, and in intense field electrodynamics. The relativistic corrections to the ponderomotive force of a transversely polarized electromagnetic wave lead to an approximately 20-percent reduction in the single particle ponderomotive force produced by a 10-?m 1016-W/cm2 laser field. Recent experimental investigations are based on using two intense laser fields to produce desired laser-matter interactions. This paper presents the first derivation of the nonlinear relativistic ponderomotive force produced by two intense laser fields. The results demonstrate that relativistic ponderomotive forces are not additive.  相似文献   

19.
A relativistic generalization of the semiclassical theory of tunneling and multiphoton ionization of atoms and ions in the field of a high-intensity electromagnetic wave with linear, circular, and elliptic polarization is constructed. The exponential factor in the ionization probability is calculated for arbitrary values of adiabaticity parameter γ. In the case of low-frequency laser radiation, an asymptotically exact formula is derived for the ionization rate of the s atomic level, including the Coulomb, spin, and adiabatic corrections and the preexponential factor.  相似文献   

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