Triplet p + ip pairing correlations in the doped Kane-Mele-Hubbard model: A quantum Monte Carlo study

• Published in: Europhysics letters Vol. 111; no. 4; pp. 47003 - p1-47003-p6
• Main Authors: Ma, Tianxing, Lin, Hai-Qing, Gubernatis, J. E.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences, IOP Publishing and Società Italiana di Fisica 01.08.2015; IOP Publishing
• Subjects: 71.10.Fd; 74.20.Mn; 74.20.Rp; Atomic properties; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Computer simulation; Correlation; Correlation analysis; Fermi surfaces; Honeycomb; Lattices; Material Science; Monte Carlo methods; Monte Carlo simulation; Optical traps; Spin-orbit interactions; Superconductivity; Symmetry; Topology; Ultracold atoms
• ISSN: 0295-5075; 1286-4854
• DOI: 10.1209/0295-5075/111/47003

By using the constrained-phase quantum Monte Carlo method, we performed a systematic study of the pairing correlations in the ground state of the doped Kane-Mele-Hubbard model on a honeycomb lattice. We find that pairing correlations with d + id symmetry dominate close to half-filling, but pairing correlations with p + ip symmetry dominate as hole doping moves the system below three-quarters filling. We correlate these behaviors of the pairing correlations with the topology of the Fermi surfaces of the non-interacting problem. We also find that the effective pairing correlation is enhanced greatly as the interaction increases, and these superconducting correlations are robust against varying the spin-orbit coupling strength. Our numerical results suggest a possible way to realize spin triplet superconductivity in doped honeycomb-like materials or ultracold atoms in optical traps.