Conductivity-Like Gilbert Damping due to Intraband Scattering in Epitaxial Iron

ORAL

Abstract

Confirming the origin of Gilbert damping by experiment has remained a challenge for many decades, even for some of the simplest ferromagnetic metals. Here, we experimentally identify Gilbert damping that increases with decreasing electronic scattering in thin films of BCC Fe. The observed conductivity-like damping, which cannot be accounted for by classical eddy current loss, is in excellent quantitative agreement with theoretical predictions of Gilbert damping due to intraband scattering. These results resolve the longstanding question since the 1970s about the role of intraband scattering in Gilbert damping. Our results also indicate that – somewhat counterintuitively – disorder can reduce intrinsic damping at low temperatures in ferromagnetic metals, such that optimally disordered films may be well suited for cryogenic spintronic and quantum applications.

*This research was funded in part by 4-VA, a collaborative partnership for advancing the Commonwealth of Virginia. A. Sapkota and C. Mewes would like to acknowledge support by NSF-CAREER Award No. 1452670, and A. Srivastava would like to acknowledge support by NASA Award No. CAN80NSSC18M0023.

Presenters

  • Satoru Emori

    • Physics, Virginia Tech
    • Virginia Tech
    • Physics, Virginia Polytechnic Institute and State University

Authors

  • Behrouz Khodadadi

    • Physics, Virginia Tech
    • Virginia Tech
  • Anish Rai

    • University of Alabama
  • Arjun Sapkota

    • University of Alabama
  • Abhishek Srivastava

    • University of Alabama
  • Bhuwan Nepal

    • University of Alabama
  • Youngmin Lim

    • Physics, Virginia Tech
    • Virginia Tech
  • David Smith

    • Virginia Tech
  • Claudia K.A. Mewes

    • University of Alabama
  • Sujan Budhathoki

    • University of Alabama
  • Adam Joseph Hauser

    • University of Alabama
  • Min Gao

    • Virginia Tech
  • Jie-Fang Li

    • Materials Science and Engineering, Virginia Tech
    • Virginia Tech
  • Dwight D Viehland

    • Materials Science and Engineering, Virginia Tech
    • Virginia Tech
  • Zijian Jiang

    • Virginia Tech
  • Jean J Heremans

    • Virginia Tech
  • Prasanna V Balachandran

    • University of Virginia
  • Tim Mewes

    • University of Alabama
  • Satoru Emori

    • Physics, Virginia Tech
    • Virginia Tech
    • Physics, Virginia Polytechnic Institute and State University