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本文利用Ge中浅施主杂质的有效质量波函数,计算了束缚电子的等效自旋哈密顿量,得到在没有外压力及内应力情况下,仅当Ge的导带极值偏离(2π)/α[111]点时,共振频率才是各向导性的。指出通过电子-核双共振实验可能较确切的判断Ge中导带极值的位置。利用畸变势理论及微扰论,计算了在一般缓变的非均匀内应力作用下,共振频率及自旋共振线宽随磁场方向的各向异性变化。最后具体计算了在以拉伸法生长的晶体中和在弯曲的范性形变下,在最主要的位错类型([211]方向刃型及[110]方向螺型位错)应力场作用下自旋共振线宽的非均匀加宽,指出对于不同类型及不同取向的位错有不同的各向异性线宽。与Wilson的实验结果比较,我们得到当位错密度小于104εcm-2时,位错应力不是形成线宽的主要原因,当磁场在不同的(110)平面内旋转时,线宽将有相似的各向异性。当位错密度大于105εcm-2时,位错应力对线宽的贡献是主要的。这很容易由实验判断。In this paper the effective mass wave function of the bound shallow donor electron in Ge was used to obtain the spin-Hamiltonian. It was shown that the resonance frequency is anisotropic only if the minima of the conduction band deviate from the symmetry points (2π)/α[111], provided there is no stress. This makes it possible to determine whether the minima of the conduction band slightly deviate from the (2π)/α[111] points ornot by means of experiments of double resonance.The general expressions of the resonance frequency and anisotropic line width were obtained by taking the smoothly varying nonhomogeneous stress as perturbation. Furthermore, we calculated in detail the nonhomogeneous broadening of the resonance line under the action of the stress of dislocations in Ge generated during the growth of single crystals by the pulling method or by means of plastic deformation (edge dislocation of the [211] direction and screw dislocation of [110]). It was pointed out that the anisotropy of line width is essentially different for different types of dislocations, and also for different equivalent directions. In comparison with the experimental results of Wilson, we concluded that, as the density of dislocation is smaller than 104εcm-2, the dislocation stress is not the main cause of broadening, so that the line width should have similar anisotropy as the magnetic field is oriented in different (110) planes. When the density is larger than 105εcm-2, dislocation stress gives the main contribution to broadening. This effect can be easily examined experimentally.
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