Cooling field and temperature dependent exchange bias in spin glass/ferromagnet bilayers

W B Rui; Y Hu; A Du; B You; M W Xiao; W Zhang; S M Zhou; J Du

doi:10.1038/srep13640

Cooling field and temperature dependent exchange bias in spin glass/ferromagnet bilayers

Sci Rep. 2015 Sep 8:5:13640. doi: 10.1038/srep13640.

Authors

W B Rui¹, Y Hu^{2

3}, A Du², B You^{1

4}, M W Xiao¹, W Zhang¹, S M Zhou⁵, J Du^{1

4}

Affiliations

¹ National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, P. R. China.
² College of Sciences, Northeastern University, Shenyang, 110819, P. R. China.
³ MOE Key Laboratory for Anisotropy and Texture of Materials, Northeastern University, Shenyang, 110819, P. R. China.
⁴ Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, P. R. China.
⁵ Department of Physics, Tongji University, Shanghai, 200092, P. R. China.

Abstract

We report on the experimental and theoretical studies of cooling field (HFC) and temperature (T) dependent exchange bias (EB) in FexAu1-x/Fe19Ni81 spin glass (SG)/ferromagnet (FM) bilayers. When x varies from 8% to 14% in the FexAu1-x SG alloys, with increasing T, a sign-changeable exchange bias field (HE) together with a unimodal distribution of coercivity (HC) are observed. Significantly, increasing in the magnitude of HFC reduces (increases) the value of HE in the negative (positive) region, resulting in the entire HE∼T curve to move leftwards and upwards. In the meanwhile, HFC variation has weak effects on HC. By Monte Carlo simulation using a SG/FM vector model, we are able to reproduce such HE dependences on T and HFC for the SG/FM system. Thus this work reveals that the SG/FM bilayer system containing intimately coupled interface, instead of a single SG layer, is responsible for the novel EB properties.

Publication types

Research Support, Non-U.S. Gov't