关键词: 量子点系统, Keldysh格林函数, Kondo效应

Abstract: Based on the infinite-U Anderson model, Keldysh Green Function was used to calculate the Kondo splitting of DOS (Density of State) in quantum dot induced by a side?coupled magnetic impurity. Because of the normalization for quantum dot energy caused by the ferromagnetic lead, the Kondo peak in DOS splits. It?s shown that the polarization of the magnetic leads and the azimuth of the impurity spin set off the Kondo resonant splitting in the DOS. For the antiparallel configuration of lead magnetization, the localization of the peaks is hardly influenced by the magnetic impurity. For the parallel configuration, three Kondo peaks appear in the DOS and the interval of the peaks depends on the impurity spin azimuth. The splitting in the DOS induced by the magnetic leads can be compensated by the side?coupled impurity, if the polarizations of the magnetic leads are choosed rightly.

Key words: quantum dot system, Keldysh green function, Kondo effect