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通过采用转移矩阵方法求解自旋电子隧穿过程,理论研究了半导体超晶格系统中电子自旋输运的磁电调控行为.结果表明:仅对超晶格系统施以磁调制,隧穿系数将出现自旋分裂,随磁场增强,电导自旋极化率变大且展宽于费米能区;若选取不变磁场情况,同时施以间隔周期电场调制,超晶格的电子极化率将有更为显著地提高.进一步发现,随电场强度的改变,电子自旋输运行为显然存在两个明显不同区域,下自旋电子将在不同调制区域表现为不同的变化趋势.然而,若对周期磁超晶格施加间隔两周期的电调制,自旋电导输运的临界行为消失,电导极化率在高能区的共振峰趋向消失.这也说明超晶格系统的对称性将可能对其磁电调控自旋输运行为产生重要影响.
By using the transfer matrix method to solve the spin-electron tunneling process, the magnetoelectronic control of electron spin transport in a semiconductor superlattice system has been studied theoretically. The results show that only magnetic modulation is applied to the superlattice system and the tunneling coefficient Will spin split, with the magnetic field increases, the conductivity of the spin-spin rate becomes larger and broadened in the Fermi region; if the invariant magnetic field conditions, while applied to the interval-period electric field modulation, the superlattice electron polarizability will be It is found that with the change of electric field intensity, there are obviously two distinct regions of electron spin transport, and the spin electrons will show different trends in different modulation regions. However, Periodic magnetic superlattices exert a two-period electrical modulation, and the critical conductance of spin-conductance transport disappears, and the conductance polarization disappears in the high-energy region. This also shows that the symmetry of the superlattice system will probably affect its Magneto-electrical control of spin transport has an important impact.