Temperature dependence of magnetoresistance in the magnetic tunnel junction with an asymmetrical barrier

✍ Scribed by Jun-Zhong Wang; Bo-Zang Li; Zhan-Ning Hu

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 127 KB
• Volume: 261
• Category: Article
• ISSN: 0375-9601
• DOI: 10.1016/s0375-9601(99)00614-3

✦ Synopsis

By considering the excitation of the spin wave at the interface between magnetic electrodes and insulating barrier and 3r2 Ž . taking the mean-field approximation to the s-d exchange interaction, a T law is derived for the temperature T dependence of the exchange field in ferromagnets. Then we have investigated the T dependence of spin-polarized tunneling in a magnetic tunnel junction with an asymmetrical barrier. It is found that the extended Slonczewski model can provide a Ž . good approximation for the T-dependence of the junction magnetoresistance JMR , a qualitative explanation for parallel tunneling conductance, and an exact description for the conductance difference between the parallel and antiparallel Ž . alignments of two electrodes DG . However, for the Julliere model, owing to the smaller contribution from interfacial states it involves, a decreasing T-dependence of the parallel conductance is derived, which is in contradiction with experimental results.