Strain induced superconducting pair-density-wave states in graphene

ORAL

Abstract

Graphene is known to be non-superconducting. However, surprising superconductivity is recently discovered in a flat-band in a twisted bi-layer graphene. Here we show that superconductivity can be more easily realized in topological flat-bands induced by strain in graphene through periodic ripples. Specifically, it is shown that by including correlation effects, the chiral d-wave superconductivity can be stabilized under strain even for slightly doped graphene. The chiral d-wave superconductivity generally coexists with charge density waves (CDW) and pair density waves (PDW) of the same period. Remarkably, a pure PDW state with doubled period that coexists with the CDW state is found to emerge at a finite temperature region under reasonable strain strength. The emergent PDW state is shown to be superconducting with non-vanishing superfluid density, and it realizes the long searched superconducting states with non-vanishing center of mass momentum for Cooper pairs.

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Presenters

  • Chung-Yu Mou

    Department of physics, National Tsing-Hua University, Departmeny of Physics, National Tsing Hua University, Hsinchu, Taiwan, Department of Physics, National Tsing Hua University, Hsinchu, Taiwan

Authors

  • Chung-Yu Mou

    Department of physics, National Tsing-Hua University, Departmeny of Physics, National Tsing Hua University, Hsinchu, Taiwan, Department of Physics, National Tsing Hua University, Hsinchu, Taiwan

  • Feng Xu

    School of Physics and Telecommunication Engineering, Shaanxi University of technology, Hanzhong, China

  • Chung-Hou Chung

    Department of Electrophysics, National Chiao-Tung University, Hsinchu, Taiwan, R.O.C., National Chiao Tung University, Department of Eletrophysics, National Chiao Tung University, Department of Electrophysics, National Chiao Tung University, Electrophysics Department, National Chiao-Tung University, Hsinchu, Taiwan, Electrophysics Department, National Chiao-Tung University, Taiwan

  • Ting-Kuo Lee

    Institute of Physics, Academia Sinica, Institute of Physics, Academia Sinica, Taiwan, Institute of physics, Academia Sinica