电子双势垒量子隧穿的散射矩阵方法及其数值模拟

Scattering matrix method and numerical simulation for electronic quantum tunneling a double-barrier

采用散射矩阵的方法研究了电子在由两个方势垒组成的双势垒结构中的隧穿特性.将电子在双势垒中的隧穿过程分为相干输运和非相干输运两部分来研究,相干输运导致了隧穿透射系数随中间层厚度变化产生量子振荡,而非相干输运导致了振荡振幅的衰减.双势垒总的透射系数与势垒高度、入射和出射波矢的匹配性有关,数值计算的结果证实了相关结论.

Using the scattering matrix method, we study the characteristics of electronic tunneling a double square barrier. Taking into account the tunneling current with ballistic and diffusive components,we present the resuits of ballistic component for oscillation of the transmission coefficient,while the diffusive one leads to decay. It is shown that the overall transmission coefficient of the double-barrier potential is related to the height of potemtial barrier and the matching of incident wave and the out wave. The conclusions are confirmed by the numerical results.