Magnetic Field Effects on Quantum-Dot Spin Valves  

作　　者：GAO Jin-Hua SUN Qing-Feng XIE Xin-Cheng 

机构地区：[1]Beijing National Lab for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China [2]Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA

出　　处：《Communications in Theoretical Physics》2009年第3期555-562,共8页理论物理通讯（英文版）

基　　金：supported by the Chinese Academy of Sciences,US-DOE under Grant No.DE-FG02-04ER46124,US-Natural Science Foundation;National Natural Science Foundation of China under Grant Nos.10525418,10734110,and 60776060

摘　　要：We study the magnetic field effects on the spin-polarized transport of the quantum dot （QD） spin valve in the sequential tunneling regime. A set of generalized master equation is derived. Based on that, we discuss the collinear and noncollinear magnetic field effects, respectively. In the collinear magnetic field case, we find that the Zeeman splitting can induce a negative differential conductance （NDC）, which is quite different from the one found in previous studies. It has a critical polarization in the parallel arrangement and will disappear in the antiparallel configuration. In the noncollinear magnetic field case, the current shows two plateaus and their angular dependence is analyzed. Although sometimes the two current plateaus have similar angular dependence, their mechanisms are different. Our formalism is also suitable for calculating the transport in magnetic molecules, in which the spin splitting is induced not by a magnetic field but by the intrinsic magnetization.

关 键 词：spin value SPINTRONICS quantum dot 

分 类 号：O484.43[理学—固体物理] TU991.22[理学—物理]