Quantum Phase Transitions in a Multi-Orbital Hubbard Model for Iron Pnictides

ORAL

Abstract

Quantum criticality in iron pnictides was proposed within an effective field theory that contains both antiferromgnetic and nematic order parameters [1,2]. Its proposed realization in P-doped BaFe2As2 has received extensive experimental evidence [3,4]. Here we study this problem within a multi-orbital Hubbard model containing both the Hubbard and Hund’s interactions. We analyze the effect of electron correlations in a non-perturbative way, through a variational Monte Carlo method that is based on a Jastrow-Slater wave function. We study the evolution of the electronic orders as the interaction strength is varied, report evidence for concurrent antiferromagnetic and nematic quantum critical points, and discuss the implications for superconducting pairing.

[1] J. Dai, Q. Si, J.-X. Zhu, and E. Abrahams, PNAS 106, 4118 (2009).
[2] J. Wu, Q. Si, and E. Abrahams, Phys. Rev. B 93, 104515 (2016).
[3] T. Shibauchi et al., Ann. Rev. Conden. Matter Phys. 5, 113 (2014).
[4] I. M. Hayes et al., Nature Phys. 12, 916 (2016).

*This work is supported by the DOE Award # DE-SC0018197 and Welch Foundation.

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Presenters

  • Wenjun Hu

    • Rice University
    • Department of Physics and Astronomy, Rice University

Authors

  • Wenjun Hu

    • Rice University
    • Department of Physics and Astronomy, Rice University

  • Luca Fausto Tocchio

    • Institute for condensed matter physics and complex systems
    • Institute for Condensed Matter Physics and Complex Systems, Politecnico di Torino, Italy

  • Hsin-Hua Lai

    • Rice University
    • Department of Physics and Astronomy, Rice University

  • Rong Yu

    • Renming University of China
    • Physics Department, Renmin University
    • Renmin University of China
    • Department of Physics, Renmin University of China

  • Federico Becca

    • International School for Advanced Studies
    • SISSA-ISAS, International School for Advanced Studies, Trieste (Italy)
    • National Research Council
    • Democritos National Simulation Center, Istituto Officina dei Materiali del CNR and International School for Advanced Studies (SISSA), Trieste, Italy

  • Qimiao Si

    • Rice University
    • Department of Physics and Astronomy, Rice University
    • Department of Physics and Astronomy, Houston, Texas 77005, USA, Rice University