Electrically controlled quantum dot based spin current injector

Abstract

We present a proposal for a fully electrically controllable quantum dot based spin current injector. The device consists of a quantum dot that is strongly coupled to a ferromagnetic electrode on one side and weakly coupled to a nonmagnetic electrode on the other side. The presence of ferromagnetic electrode results in an exchange field that splits the dot level. We show that this exchange-induced splitting can lead to almost full spin polarization of the current flowing through the device. Moreover, we also demonstrate that the sign of the polarization can be changed by the gate or the bias voltage within a switching time in the nanosecond range. Thus the proposed device can operate as an electrically controlled, fast switchable spin current source, which can be realized in various state-of-the-art nanostructures.

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Cited by in corpus (4)

• Superconducting proximity effect and zero-bias anomaly in transport through quantum dots weakly attached to ferromagnetic leads
• Perfect spin polarization in T-shaped double quantum dots due to the spin-dependent Fano effect
• Full electrostatic control over polarized currents through spin-orbital Kondo effect
• Quantum interference hybrid spin-current injector