Abstract
The temperature dependence of resistance in parallel (P) and antiparallel (AP) configurations (RP,AP) has been investigated in epitaxial Fe/MgO/Fe junctions with varying MgO barrier thicknesses tMgO. RAP exhibits a substantial decrease with increasing temperature for samples with tMgO ranging from 3.0 to 1.5 nm. In contrast, RP is approximately temperature independent when tMgO =3.0 nm and increases with temperature when tMgO =2.1 and 1.5 nm. Possible origins of this temperature dependence of resistance, which include taking into account a spin independent term and consideration of spin-flip scattering, are discussed. We attribute the temperature dependence of RP,AP to the misalignment of magnetic moments in the electrodes due to thermal excitations and its effect on the spin dependent tunneling.
Original language | English |
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Article number | 052506 |
Journal | Applied Physics Letters |
Volume | 95 |
Issue number | 5 |
DOIs | |
State | Published - 2009 |
Externally published | Yes |
Funding
The project is supported by the National Basic Research Program of China (Grant No. 2009CB929203) and the State Key Project of Fundamental Research of Ministry of Science and Technology (Grant No. 2006CB932200) and National Natural Science Foundation (Grant Nos. 10874225, 50721001, and 60871048). Partial support is from the joint projects of NSFC-the Royal Society (U.K.), NSFC-Australia DEST, and K. C. Wong Education Foundation, Hong Kong. S.G.W. is grateful to the Engineering and Physical Sciences Research Council of U.K. for financial support.