Angle dependence of <i>H</i><sub>c2</sub> with crossover between the orbital and paramagnetic limits in 2D NbSe<sub>2</sub>

ORAL

Abstract

Transition metal dichalcogenides (TMDs) are layered materials of abundant variety, providing emergent two-dimensional (2D) physical phenomena such as 2D superconductivity in few-layer NbSe2. In the previous APS March Meeting, we reported layer-by-layer MBE growth of NbSe2 thin films on insulating sapphire substrates [1], achieving relatively high Tc comparable to that of bulk in the thick-enough regime. With reducing thickness, superconducting properties turned out to exhibit 2D-like behavior, realizing Ising superconductivity with large-area samples. In this presentation, we will present the experimental data on the angle dependence of Hc2 in a bilayer NbSe2 film measured with a 55 T pulsed magnet at 3He temperature. We observed cusp-like angle dependence of Hc2 around the parallel magnetic fields even far below Tc despite that Hc2 is purely dominated by the paramagnetic effect in this regime. In order to explain those results, we will propose a generalized Ginzburg-Landau model by taking into account the paramagnetic effect, which well describes the results with a microscopic physical picture. [1] H. Matsuoka et al, APS March Meeting 2018, K35.00009.

Presenters

  • Hideki Matsuoka

    • Univ of Tokyo
    • Department of Applied Physics, The University of Tokyo

Authors

  • Hideki Matsuoka

    • Univ of Tokyo
    • Department of Applied Physics, The University of Tokyo
  • Masaki Nakano

    • Univ of Tokyo
    • Department of Applied Physics, The University of Tokyo
  • Takashi Shitaokoshi

    • ISSP, The University of Tokyo
  • Takumi Ouchi

    • Tohoku Univ., Sendai, Japan.
    • IMR, Tohoku Univ.
  • Yue Wang

    • Univ of Tokyo
    • Department of Applied Physics, The University of Tokyo
  • Yuta Kashiwabara

    • Univ of Tokyo
  • Satoshi Yoshida

    • Univ of Tokyo
  • Kyoko Ishizaka

    • Univ of Tokyo
    • Department of Applied Physics, University of Tokyo
  • Masashi Kawasaki

    • Univ of Tokyo
    • University of Tokyo
    • Department of Applied Physics, Univ of Tokyo
  • Yoshimitsu Kohama

    • Tokyo University
    • University of Tokyo
    • Univ. of Tokyo
    • ISSP, The University of Tokyo
  • Tsutomu Nojima

    • Tohoku Univ., Sendai, Japan.
    • IMR, Tohoku Univ.
  • Yoshihiro Iwasa

    • Department of Applied Physics, The University of Tokyo
    • Univ of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics (QPEC) Center, The University of Tokyo
    • The Univ. of Tokyo, Tokyo, Japan.
    • The University of Tokyo
    • Applied Physics, the University of Tokyo