Pumping Spin and Charge Currents from Applying a Time-Variant Field and a Magnetic Field to a Quantum Dot

Abstract:

Photon-electron pumping effects on a quantum dot connected to two magnetic leads in the presence of both via-dot and over-dot tunneling channels have been investigated by the evolution operator approach. It is found that a time-variant field applied to the quantum dot may give rise to charge and spin pumping at zero bias voltage for asymmetric magnetic junctions. When the magnetic field switch on，the spin-up and spin-down current can be considerably separated，then the highly spin polarized current is also generated.

• Periodical: Key Engineering Materials (Volumes 480-481)
• Pages: 1446-1451
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.480-481.1446
• Online since: June 2011
• Authors: Jian Ming Yao
• Keywords: Charge Current, Evolution Operator Approach, Quantum Dot (QD), Spin Current, Time-Variant Field

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