title: Correlation effects in quantum spin-Hall insulators: a quantum Monte Carlo study.
abstract: We consider the Kane-Mele model supplemented by a Hubbard U term. The phase diagram is mapped out using projective auxiliary field quantum Monte Carlo simulations. The quantum spin liquid of the Hubbard model is robust against weak spin-orbit interaction, and is not adiabatically connected to the spin-Hall insulating state. Beyond a critical value of U>U(c) both states are unstable toward magnetic ordering. In the quantum spin-Hall state we study the spin, charge, and single-particle dynamics of the helical Luttinger liquid by retaining the Hubbard interaction only on a ribbon edge. The Hubbard interaction greatly suppresses charge currents along the edge and promotes edge magnetism but leaves the single-particle signatures of the helical liquid intact.
authors.affiliation: Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Hohenadler
authors.forename: T C
authors.initials: TC
authors.lastname: Lang
authors.forename: F F
authors.initials: FF
authors.lastname: Assaad