硅中空穴与核的超精细作用及p型硅的核磁弛豫

本文把半导体中载流子和它的原子核的超精细作用(包括非接触项)表达为作用在有效质量波函数上的“准接触作用”。具体对硅中Si²⁹核和价带空穴的这个作用可表达为{S₁(J_xμ_nx+J_yμ_ny+J_zμ_nz)+S₂(J_x³μ_nx+J_y³μ_ny+J_z³μ_nz)}δ(r-r_n),参量S₁、S₂是联系着价带顶的波函数的一些积分;一般地S₂≈0。用它来处理了p型硅中Si²⁹核的核自旋弛豫,得到弛豫时间的表达式;从弛豫时间的实验值估计了S₁的值;还从价带自旋轨道分裂值估计了同一参量。

THE HYPERFINE INTERACTION BETWEEN NUCLEONS AND HOLES OF SILICON, AND THE NUCLEAR MAGNETIC RELAXATION IN THE p-TYPE SILICON

The hyperfine interaction of the carriers in semiconductors (involving the Fermi-contact and noncontact terms) has been treated by a "pseudo-contact interaction", which acts on the effective mass wavefunction. For the Si²⁹ nucleons and the holes in silicon, it can be represented by {S₁(J_xμ_nx+J_yμ_ny+J_zμ_nz)+S₂(J_x³μ_nx+J_y³μ_ny+J_z³μ_nz)}δ(r-r_n). The coupling parameters S₁ and S₂ are certain integrals connecting the Bloch functions of the top of the value band, generally S₂≈0. Utilizing the above formula we have treated the nuclear magnetic relaxation in p-type silicon and obtained an expression for the relaxation time; the value of the parameter S₁ has been determined from the relaxation time and from the spin orbit splitting value at the valence band top.