反比相关的双曲余弦平方势与相对论电子面沟道辐射的经典描述

在经典力学框架内,描述了带电粒子自发辐射谱分布与最大辐射频率;引入反比相关的双曲余弦平方势,讨论了超相对论电子的面沟道辐射,导出了电子能量E=5.0GeV时,一次谐波的最大辐射能量ε=57MeV,与其他工作比较基本一致.沟道辐射与自由电子激光十分类似,它的方向性极好,大都集中在粒子运动方向、角宽Δθ≈γ^-1/2范围内;且能量高、连续可调,偏振度也很好.指出了利用超晶格沟道辐射与超晶格的多层薄膜结构相互作用,可望把自发的沟道辐射改造为相干辐射,从而得到X激光或γ激光.     

正电子面沟道辐射的非线性特征

经典物理学指出,在电磁场中作加速运动的带电粒子将不断向外辐射能量.在晶体沟道中运动的带电粒子也不例外,晶格场可以使带电粒子的辐射能量达到很高.对于10MeV的正电子,辐射能量可达keV量级.粒子在沟道中的运动行为决定于粒子晶体的相互作用势,常用的相互作用势有Lindhard势、Moliere势和正弦平方势.由于粒子在沟道中的运动行为十分类似于震荡器中运动的自由电子,可望把沟道辐射改造为Χ射线激光或γ射线激光.从Lindhard势出发,将其展开到四次项,在经典力学框架内,粒子的运动方程可以化为含立方项的二阶非线性微分方程,并利用Jacobian椭圆函数和第一类全椭圆积分解析地表示了系统的解和粒子运动周期,导出了正电子面沟道辐射的瞬时辐射强度、平均辐射强度和最大辐射频率,指出了利用沟道辐射作为γ激光的可能性.     

超晶格量子阱作为光学双稳态器件的相平面特征及其稳定性

辐射强度与量子阱沟道的接受度有关,而接受度的大小则直接取决于量子阱宽度、深度以及电子束流的品质等因素.电子束可以用离子注入机或加速器提供,也可以用电压偏置的方法来获得.利用加速器理论中的相平面分析方法,分析了这种双稳态系统的相平面特征及其稳定性.引入正弦平方势,在经典力学框架内和电压偏置情况下,把粒子运动方程化为具有固定力矩的摆方程,用Jacobian椭圆函数和第一类椭圆积分解析地给出了无扰动系统的解和振动周期,并用数值方法分析了扰动情况下的相平面特征和系统的稳定性.为超晶格量子阱光学双稳态器件的设计提供了基本的理论分析.     

引入反比相关双曲余弦平方势描述超晶格量子阱的电子跃迁

 鉴于“方形”势阱过于简单和理想，引入了反比相关双曲余弦平方势描述超晶格量子阱中的电子运动行为。在量子力学框架内，把电子的Schrodinger方程化为了超几何方程, 并以Ga^1-xAl^xAs-GaAs- Ga^1-xAl^xAs量子阱为例计算了电子的带内跃迁和带间跃迁。结果表明，能级数目和跃迁能量与阱深、阱宽等系统参数有关，只需适当调节这些参数就可望实现对超晶格量子阱光电特征的调节与控制。     

ZnS／ZnSe多量子阱的光调制测试

以DMZn、H2Se和H2S为源，用Ap-MOCVD法在GaAs(100)衬底上生长出了ZnS／ZnSe超晶格量子阱，并用X射线衍射等方法鉴定了超晶格量子阱结构，在带蚀孔的衬底的ZnS／ZnSe超晶格量子阱上，首次观测到皮秒量级的光光调制现象。     

Schrdinger方程的一般解与超晶格多量子阱的电子跃迁

假设超晶格量子阱是一个形状任意的周期势阱,电子在超晶格中的运动问题可视为周期场中的运动问题.在量子力学的框架内,从Schr dinger方程和它的一般解出发,利用Bloch理论和传输矩阵方法导出了系统的色散方程;在抛物线近似下,讨论了超晶格量子阱的电子跃迁.结果表明,辐射能量位于红外、远红外或太赫兹波段.     

正弦平方势与小振幅近似下的弯晶沟道辐射

在理想情况下和经典力学框架内,引入正弦平方势,把粒子在弯晶中的运动方程化为具有外力矩的摆方程。并对系统的相平面特征进行了数值分析。在小振幅近似下,把粒子运动方程化为具有硬特性的弹簧-振子系统,用Jacobian椭圆函数和椭圆积分解析地给出系统的解和粒子运动周期。讨论了弯晶沟道辐射频率、无量纲偏转角和辐射谱的一般特征。指出利用沟道辐射作为激光的可能性。以正电子在碳单晶中沟道辐射为例进行了具体计算,得到了与其他工作基本一致的结果。     

正弦平方势与沟道辐射谱线的自然展宽

指出了非线性效应、多普勒效应、晶格热振动、电子多重散射和偶极效应等对沟道辐射谱线宽度的影响;强调了辐射反作用对谱线宽度的影响是不可避免的。比较了不同的粒子-晶体相互作用势,并从正弦平方势出发,在小振幅近似下讨论了沟道粒子的运动行为;用摄动法求解了系统的特征方程,计算了沟道辐射谱线的自然展宽和频率漂移。最后,以正电子的Si(110)面沟道辐射为例,计算了它的辐射频率。结果表明,对于能量为E=56MeV的正电子,沟道辐射能量E=ω=36.0keV。     

正弦平方势与正电子面沟道辐射的一般特征

引入正弦平方势，在经典力学框架内，将面沟道粒子的运动方程化为标准的摆方程，并用Jacobian椭圆函数和椭圆积分解析地给出系统的解和粒子运动周期，导出了正电子面沟道辐射的瞬时辐射强度、平均辐射强度和辐射谱特征.结果表明，沟道辐射频率己进入γ-能区，并指出了利用它作为短波长激光的可能性. 关键词： 沟道辐射 非线性 正弦平方势     

超晶格量子阱的沟道辐射及其谱分布

在经典物理框架内和偶极近似下, 导出了超晶格量子阱沟道辐射频率和辐射谱分布。指出了对于自发辐射谱分布, 存在一个普适的线型因子, 而粒子的最大辐射能量与相对论因子γ 有关, 且与γ3/2成正比。以正弦平方势为例进行了具体讨论。结果表明, 由于势阱深度和噪音的影响, 谐波数l只取少数几个值。超晶格量子阱沟道辐射只存在不多的几条谱线, 为进一步应用提供了可能。最后, 还给出了一种可能的实验方案, 讨论了如何利用弯晶把超晶格量子阱的沟道辐射改造为相干辐射。 In the frame of classical physics and the dipole approximation the radiation frequency and the spectral distribution are derived for the channeling radiation of a charged particle in a superlattice quantum well. It indicated that there is a line type factor f(ξ) suited to various cases in the spontaneous radiations spectrum. Results also show that the maximum radiation energy is proportional to γ3/2 , but the relativistic effects have double effects in the spontaneous radiation of a charged particle. The case for the sine squared potential is discussed specifically. The harmonic number can be defined as a few variable values by the effects of the potential well depth and noise. In general there is a few spectral lines in the channeling radiation spectrum for the superlattice quantum well, and possibilities are provided for further application. Finally, a possible experimental scheme is proposed, and it is discussed that how to transform the channeling radiation in the quantum well into the cohenent radiation by the bent crystal.     

The nature of empirical constants in the equation relating the frequency of the stretching vibration of oh-groups to parameters of the [MO n ]-polyhedrons coordinating these groups

Institute of Physicoorganic Chemistry, Academy of Sciences of Belarus, 220603, Minsk, Ul. Surganova, 13, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 1, pp. 104–107, January–February, 1995.     

Effect of oxygen on the optical properties of ZnSe in the region of 0.44–20 μm

Moscow Power Engineering Institute, 14, Krasnokazarmennaya Str., Moscow, GSP, 105835, Russia. Translated from Zhurnal Prikladnois Spektroskopii, Vol. 63, No. 4, pp. 646–651, July–August, 1996.     

Energy transfer as a method for investigation of the structure of electrolytes

S. I. Vavilov State Optical Institute, Russia, 199034, St. Peterburg, Birzhevaya Liniya, 12. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 3, pp. 38–42, May–June, 1995.     

Optical properties of pure and doped Y3Fe5O12 single crystals

Institute of Physics of Solids and Semiconductors, Academy of Sciences of Belarus, 17, P. Brovka Str., GSP, Minsk, 220072. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 63, No. 4, pp. 667–675, July–August, 1996.     

Spectral methods for estimating the state of winter RYE sowings

We present the results of comprehensive investigations that include remote spectral measurements under field conditions, laboratory experiments, and mathematical simulation of the radiative regime of winter rye sowings. B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 5, pp. 646–650, September–October, 1997.     

Properties of zinc sulfide luminophores in thin-film structures

Ul'yanovsk State Technical University, 32, Severnyi Venets St., Ul'yanovsk, 432027, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 3, pp. 182–185, May–June, 1995.     

Atomic-emission spectrum analysis of soil

A method of the atomic-emission spectrum analysis of soil has been developed for control of the accumulation of technogenic impurities in environmental objects. A sample, after calcination at 550°C, is evaporated in an arc discharge. Spectra are recorded by a DFS-8 spectrograph. Simultaneously, determination is made of Li, Ba, Sr, Cu, Zn, Cr, Ni, Co, Pb, Bi, Mo, V, Ge, Ga, Y, Nb, Sn, Cd. For the majority of the elements the detection limits are lower than their percent abundance in the crust and their maximum permissible concentrations. Institute for Single Crystals, National Academy of Sciences of Ukraine, 60, Lenin Ave., Khar'kov, 310001, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 3, pp. 396–399, May–June, 1997.     

The effect of complexing processes on energy transfer Tl+→Gd3+ and Tl+→Tb3+ in glass

T. Shevchenko Kiev University, 252022 Kiev, Pr. Akad. Glushakova, 6, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 3, pp. 192–196, May–June, 1995.     

Luminescence of O2−-vacancy centers in BaFBr and BaFCl

Irkutsk State University, 20, Gagarin Av., Irkutsk, 664003, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 3, pp. 215–217, May–June, 1995.     

Luminescence of quantum-dimensional centers with spatially ordered molecules of organic compounds adsorbed on their surfaces

I. I. Mechnikov Odessa State University, 27, Pasteur Str., Odessa, 270100, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 3, pp. 42–48, May–June, 1995.