g-factor-enhanced upper critical field in Superconducting PdTe2 due to qauntum confinement.

ORAL

Abstract

PdTe2 is reported to be a Type-II Ising superconductor. In ultra-thin flakes, its upper critical field can exceed the Pauli limit by more than 7 times. [1] In weak coupling BCS theory, it is known that the Pauli limit is derived by equating the condensation energy of superconducting energy and free energy of spin paramagnetic effect with g-factor being 2. Here we report the enhancement of the upper critical field of thin films of PdTe2 of intermediate thickness, ranging from 30nm to 19nm . The films are grown by chemical vapor deposition. We have conducted magnetotransport measurements down to 20mK and extracted both the in-plane and out-of-plane upper critical field. We have seen the enhancement of the in-plane critical field by more than 20 times with decreasing thickness. We attribute this enhancement to a thickness-dependent change in effective g-factor, due to quantum confinement in the PdTe2, which drives an enhancement of the Pauli limit. We rule out a potential origin of Hc2 enhancement related to impurities by studying the residual resistivity ratio and the lateral grain size of films of different thickness.

*K.Y., T.C.H, X.L., X.L., Y.T.H. and B.A.A acknowledge Department of Energy Basic Energy Science Award DE-SC0024291. D.V.C. acknowledges financial support from the National High Magnetic Field Laboratory through a Dirac Fellowship. H.M. and C.L. are supported by start-up funds from Florida State University and the National High Magnetic Field Laboratory. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreements No. DMR-1644779, No. DMR-2128556, and the State of Florida. D. J. and S. Z. acknowledge support from the Department of Energy (DOE) under Award No. DE-SC0025542. The work at NIMS (growth recipe development) was supported by JSPS KAKENHI Grants No. 25K22210, 24H01210, 24H02218, 23H05469, JST SCICORP Grant No. JPMJSC2110 and World Premier International Research Center Initiative (WPI), MEXT, Japan. We also acknowledge discussions with B. Janko.

–

Presenters

  • Kota Yoshimura

    • University of Notre Dame

Authors

  • Kota Yoshimura

    • University of Notre Dame

  • Tzu-Chi Hsieh

    • University of Notre Dame

  • Huiyang Ma

    • Florida State University

  • Dmitry V Chichinadze

    • Washington University in St. Louis
    • National High Magnetic Field Laboratory

  • Shan Zou

    • Univeristy of Notre Dame

  • Michael Stuckert

    • Univeristy of Notre Dame

  • David E Graf

    • Florida State University
    • National High Magnetic Field Lab
    • National High Magnetic Field Laboratory
    • National High Magnetic Field Laboratory, Florida State University

  • Robert Nowell

    • Florida State University

  • Muhsin Abdul Karim

    • University of Notre Dame

  • Daichi Kozawa

    • National Institute for aterial Science

  • Ryo Kitaura

    • National Institute for Materials Science

  • Xiaolong Liu

    • University of Notre Dame

  • Xinyu Liu

    • University of Notre Dame

  • Dafei Jin

    • Department of Physics and Astronomy, University of Notre Dame
    • Univeristy of Notre Dame

  • Cyprian Lewandowski

    • Florida State University
    • National High Magnetic Field Laboratory

  • Yi-Ting Hsu

    • University of Notre Dame

  • Badih A Assaf

    • University of Notre Dame