电子横向运动对共振隧穿的影响

讨论了电子横纵方向运动耦合时的隧穿现象，对CdSe/Zn1-xCdxSe方形双势垒结构和抛物形双势垒结构的数值计算表明，在零偏压和非零偏压情况下，电子横向运动对共振隧穿的影响是不容忽略的。

Influence of Electron Transverse Motion on Resonant Tunneling

The aim of this paper is to explore the effect of coupling between the transverse motion and the longitudinal motion of an electron on the resonant tunneling characteristics in a multibarrier heterostructure.A method developed in a previous paper is extended to derive the related formula for the transmission coefficients depending on both the transverse wave number and the longitudinal kinetic energy of an incident electron.A static field is introduced to discuss the influence of the bias voltage on the transmission coefficients,and also to investigate the effect of the coupling between the components of the motion of an electron in the directions of parallel and perpendicular to the interface.A numerical calculation is carried out for the rectangular and parabolic barrier heterostructures consisting of CdSe/Zn 1- x Cd x Se.In the case of without a bias voltage,it is found that the coupling effect not only leads to a move of the resonant peaks toward the low energy region,but also causes the broadening of the resonant peaks and the reduction of the peak to valley ratio in the transmission spectrum.The influence of the transverse motion of an electron on the higher lying resonant states for the resonant tunneling is more remarkable than that on the lower lying resonant states.When the bias voltage is non zero,a same conclusion is obtained:the resonant peaks also move towards the high energy region.In addition, when the transverse wave number is constant,the resonant peaks also move towards the low energy region.Furthermore,the resonant peaks in the lower region will disappear as the bias voltage increases.It is shown that the coupling between components of the motion of the electron in direction parallel and perpendicular to the interface is significant for the resonant tunneling.