Quantum oscillations in the high-Tc tetragonal phase of FeSe<sub>1-x</sub>S<sub>x</sub> tuned by applied hydrostatic pressure

ORAL

Abstract

Bulk FeSe suffers a remarkable four-fold enhancement in its critical temperature under hydrostatic pressure. Furthermore, combined chemical and applied pressure in FeSe1-xSx provides important tuning parameters of the phase boundaries between the competing nematic and magnetic phases from which superconductivity emerges. While the isoelectronic substitution leads to the suppression of the nematic order in the vicinity of x~0.170(5), the applied hydrostatic pressure gives additional access to the tetragonal high-pressure phase. We present a quantum oscillations study in magnetic fields up to 45T under applied hydrostatic pressure up to 22kbar and determine the evolution of the Fermi surface and electronic correlations inside the high-Tc tetragonal phase. We detect a monotonous increase in the sizes of the different Fermi surface pockets inside the tetragonal phase, whereas the electronic correlations remain relatively unaffected.

*This work was supported by the Engineering and Physical Sciences Research Council (EP/I004475/1, EP/I017836/1, EP/M020517/1), the National Science Foundation (DMR-1157490, DMR-1644779), the State of Florida, and the Oxford Centre for Applied Superconductivity (CFAS).

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Presenters

  • Zachary Zajicek

    • Clarendon Laboratory, University of Oxford

Authors

  • Zachary Zajicek

    • Clarendon Laboratory, University of Oxford

  • Pascal Reiss

    • Clarendon Laboratory, University of Oxford

  • David E Graf

    • National High Magnetic Field Laboratory
    • Florida State University
    • National High Magnetic Field Lab, Florida State University
    • National High Magnetic Field Laboratory, Tallahassee and Florida State University
    • National High Magnetic Field Laboratory, Florida State University
    • National High Magnetic Field Laboratory (FSU)
    • Department of Physics, Florida State University
    • National High Magnetic Field Laboratory and Department of Physics, Florida State University
    • National High Magnetic Field Lab
    • National High Magnetic Field Laboratory, Tallahassee, FL
    • CMS, National High Magnetic Laboratory

  • Amir-Abbas Haghighirad

    • Karlsruhe Institute of Technology
    • Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology

  • Amalia Coldea

    • Clarendon Laboratory, University of Oxford