TY - JOUR
T1 - A novel superconductivity in Ir oxides with a large spin-orbit coupling
AU - Watanabe, Hiroshi
AU - Shirakawa, Tomonori
AU - Yunoki, Seiji
PY - 2013/7
Y1 - 2013/7
N2 - 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 dx2-y2-wave "pseudospin singlet" pairing.
AB - 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 dx2-y2-wave "pseudospin singlet" pairing.
KW - J = 1/2
KW - Pseudospin-singlet superconductivity
KW - Spin-orbit coupling
KW - SrIrO
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U2 - 10.3938/jkps.62.1848
DO - 10.3938/jkps.62.1848
M3 - Article
AN - SCOPUS:84880022660
VL - 62
SP - 1848
EP - 1851
JO - Journal of the Korean Physical Society
JF - Journal of the Korean Physical Society
SN - 0374-4884
IS - 12
ER -