Oscillatory spin pumping in Nb/NiFe/Nb junctions

ORAL

Abstract

The quantum size-induced oscilating physical phenomena has attracted a lot of interest in condensed matter physics and materials science. In this talk, I will discuss the oscillatory spin pumping in the Nb(100nm)/NiFe/Nb(100nm) trilayer structure. In the normal state of Nb, via systematical varying the thickness of NiFe from 5nm to 20nm, an oscillating Gilbert damping is observed. This oscillating behavior can be attributed to the quantum-interference effect of angular momentum transfer between the local precessing magnetic moment and conduction electrons in thin NiFe that was theoretically predicted by Mills [1]. As the NiFe layer is thin and coupled to nonmagnetic Nb layers, quantum-interference effect of the spin-polarized electrons shows up, which gives rise to the oscillating spin-transfer torque to the NiFe. This oscillating feature is observed to be largely enhanced below the superconducting critical temperatures in the Nb/NiFe/Nb Junctions.
[1]D. L. Mills, Phys. Rev. B 68, 014419 (2003).

*Y.Y., and W.H. acknowledge the financial support from NBRP (No. 2015CB921104) and NNSF (No. 11574006) of China, Beijing NSF (No. 1192009). Y.T. and S.M. acknowledge the financial support from ERATO- JST (JPMJER1402), and KAKENHI ( No. JP16H04023, and No. JP26247063) from MEXT, Japan.

Presenters

  • Yunyan Yao

    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • Department of physics, ICQM, Peking University

Authors

  • Yunyan Yao

    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • Department of physics, ICQM, Peking University

  • Ranran Cai

    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • Department of physics, ICQM, Peking University

  • Yasumasa Tsutsumi

    • RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan.

  • Yang Ma

    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • Peking Univ
    • Department of physics, ICQM, Peking University

  • Wenyu Xing

    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • Department of physics, ICQM, Peking University

  • yuan ji

    • ICQM, Peking Univ. Beijing 100871, P. R. China.

  • Xincheng Xie

    • Peking University
    • International Center for Quantum Materials, School of Physics, Peking University, China
    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • School of Physics, Peking University
    • Department of physics, ICQM, Peking University

  • See-Hun Yang

    • IBM Research, Almaden
    • IBM Almaden Res Ctr
    • IBM Research - Almaden, San Jose, California 95120, USA.

  • Sadamichi Maekawa

    • RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan.

  • Wei Han

    • ICQM, Peking Univ. Beijing 100871, P. R. China.
    • Department of physics, ICQM, Peking University