电场下量子阱的子能带和光跃迁

在稳定态的假设下,将超晶格的有效质量理论推广到有电场的情形。在隧道穿透比较小的情况下,得到了与隧道共振方法一致的结果。系统地计算了电场下宽量子阱中量子态子能级、波函数和光学矩阵元。发现量子阱中第二激发态的粒子密度偏移和能量位移与基态相反。在电场下,子能带基本形状不变,二重简并解除。随着电场增大,△n=0跃迁选择定则将被△n=±1代替,这种转变发生在中等大小的电场下。 关键词：

SUBBANDS AND OPTICAL TRANSITIONS OF SUPERLATTICES IN ELECTRIC FIELD

On the assumption of stationary states, the effective mass theory is extended to the of superlattices in electric field. When the tunnel penetration factors are small, the calculation results are in agreement with those of tunnel resonance method. Subbands, wavefunc-tions and optical matrix elements are calculated. It is found that the shifts of particle densities and energies of the second excited states are opposite to that of ground states. In the electric field the overall shape of subbands is close to that without electric field but the double degeneracy is removed. With the increase of electric field, the selection rule △n=0 goes over to △n =±1 gradually, this change-over occurs at moderate electric field.