Spin-polarized transport in ferromagnet/Rashba quantum dot/ferromagnet system

The transport properties of the Datta and Das's spin transistor with the center normal region (or the quantum dot) having Rashba spin–orbit interaction and electron–electron (e–e) interaction U are investigated. We find while intra-dot level is near or above the chemical potential of the leads, the modulation efficiency of this spin transistor almost is not influenced by U. On the other hand, when the level is below the chemical potential, e–e interaction U may affect the modulator efficiency, because in this case the existence of e–e interaction can change the transport properties of the quantum dot. But the modulation efficiency still keep enough large and the spin transistor can effectively work.