A novel superconductivity in Ir oxides with a large spin-orbit coupling

作者:Watanabe Hiroshi*; Shirakawa Tomonori; Yunoki Seiji
来源:Journal of the Korean Physical Society, 2013, 62(12): 1848-1851.
DOI:10.3938/jkps.62.1848

摘要

Motivated by novel 5d-electron systems such as Sr2IrO4 and Ba2IrO4, we study the ground state of a three-orbital Hubbard model with a spin-orbit coupling by using a variational Monte Carlo method. The obtained ground-state phase diagram reveals that an antiferromagnetic state, stable at around the electron density n = 5, is destabilized by carrier doping and that the ground state becomes superconducting. Similar to high-T (c) cuprates, a large asymmetry of the phase diagram between electron doping (n > 5) and hole doping (n < 5) is also found, which can be understood as the band structure effect. Due to the large spin-orbit coupling which entangles spin and orbital degrees of freedom, the pseudospin becomes a good quantum number, and the superconductivity found here is characterized by the -wave "pseudospin singlet" pairing.

  • 出版日期2013-7

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