Quantum theory of tunneling magnetoresistance in GaMnAs/GaAs/GaMnAs heterostructures

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:305

Article

Saffarzadeh, Alireza ; Shokri, Ali A.

关键词: diluted magnetic semiconductor;    tunnel magnetoresistance;    spin-polarized transport;   

DOI  :  10.1016/j.jmmm.2005.12.001

来源: Elsevier

【 摘 要 】

Using a quantum theory including spin-splitting effect in diluted magnetic semiconductors, we study the dependence of tunneling magnetoresistance (TMR) on barrier thickness, temperature and applied voltage in GaMnAs/GaAs/GaMnAs heterostructures. TMR ratios more than 65% are obtained at zero temperature, when one GaAs monolayer (approximate to 0.565 nm) is used as a tunnel barrier. It is also shown that the TMR ratio decreases rapidly with increasing barrier thickness and applied voltage; however, at high voltages and low thicknesses, the TMR first increases and then decreases. Our model calculations well explain the main features of the recent experimental observations. (c) 2005 Elsevier B.V. All rights reserved.

【 授权许可】

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