与铁磁体耦合的分子结中电流生热性质研究

摘要

研究与两个铁磁导体耦合的分子结中电流的生热性质.发现当分子结的能级为零时,电流和热流在不同电压下随着两个铁磁体磁化强度的增加而单调变小.当两个铁磁体的磁化方向相互反平行时,电子的入射和透射隧穿速率随磁化强度的增大而变得相差更大,从而使得电流和热流被抑制的趋势更为明显.当电压取固定值时,电流和热流在不同的分子结能级条件下随着铁磁体磁化强度的增大而变小.同样地,当两个铁磁体的磁化方向为反平行时,电流和热流被抑制的趋势更为明显.%Heat generation in a molecular junction coupled to two ferromagnetic leads is studied.It is found that when the junction level is located at zero, both the heat generation and the current decrease with increasing spin polarization in the leads.When the leads′ magnetisms are in antiparallel configuration, the difference between the electron′s incoming and outgoing tunneling rates is enlarged, resulting in more obvious suppression effect of the heat generation and electric current.For fixed bias voltage, both the electric current and heat generation also decrease with increasing spin polarization of the leads.Similarly, when the leads′ magnetisms are in antiparallel configuration, the suppression of the electric current and heat generation becomes more obvious as compared to the parallel case.