Publication Date:
2016-07-22
Description:
Author(s): A. Hojem, D. Wesenberg, and B. L. Zink In a wide range of experiments where electrical currents are used to inject angular momentum, or spin currents, from a metallic ferromagnet into a nonmagnetic metal, the interface plays a critical role. Whether in the giant magnetoresistance effect or in nonlocal spin valves, a loss of spin polarization of an electrical current crossing the interface is seen to reduce the spin current and lead to smaller overall response in sensors. The authors here compare electrical spin injection to the more recently discovered thermal spin injection in a nonlocal spin valve. They show that, despite a strong reduction of electrical spin injection that they tie to the loss of interfacial spin polarization, thermal spin injection remains a large effect. This highlights that thermal spin injection (also called the spin-dependent Seebeck effect) can proceed by new physical mechanisms not possible in the electrically driven case, potentially involving incoherent spin pumping and collective behavior of magnetization in the oxidized interface layer. Better understanding of these interface effects could lead to new ways to increase sensitivity of next-generation magnetic sensors and efficiency of sources of spin current in metallic systems. [Phys. Rev. B 94, 024426] Published Thu Jul 21, 2016
Keywords:
Magnetism
Print ISSN:
1098-0121
Electronic ISSN:
1095-3795
Topics:
Physics
Permalink
