Work

Unambiguous separation of the inverse spin Hall and anomalous Nernst effects within a ferromagnetic metal using the spin Seebeck effect

Year: 2014

Type: article

Abstract: The longitudinal spin Seebeck effect is measured on the ferromagnetic insulator Fe3O4 with the ferromagnetic metal Co0.2Fe0.6B0.2 (CoFeB) as the spin detector. By using a non-magnetic spacer material between the two materials (Ti), it is possible to decouple the two ferromagnetic materials and directly observe pure spin flow from Fe3O4 into CoFeB. It is shown that in a single ferromagnetic metal, the inverse spin Hall effect (ISHE) and anomalous Nernst effect (ANE) can occur simultaneously with opposite polarity. Using this and the large difference in the coercive fields between the two magnets, it is possible to unambiguously separate the contributions of the spin Seebeck effect from the ANE and observe the degree to which each effect contributes to the total response. These experiments show conclusively that the ISHE and ANE in CoFeB are separate phenomena with different origins and can coexist in the same material with opposite response to a thermal gradient.

Source: Applied Physics Letters

DOI: 10.1063/1.4895034

Authors: Stephen M. Wu, Jason Hoffman, John E. Pearson, Anand Bhattacharya

Institution: Argonne National Laboratory

Language: English

Topic: Magnetic properties of thin films

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funders: U.S. Department of Energy, Office of Science, Basic Energy Sciences