Statistics of holes and nature of superfluid phases in Quantum dimer models.

C. A. LAMAS, A. RALKO, M. OSHIKAWA, D. POILBLANC, P. PUJOL

Buenos Aires

Workshop; X-LAW3M; 2013

Quantum Dimer Models (QDM) arise as low energy effective models for frustrated mag-nets. Some of these models have proven successful in generating a scenario for exotic spinliquid phases with deconfined spinons. Doping, i.e. the introduction of mobile holes, hasbeen considered within the QDM framework and partially studied[2]. A fundamental issueis the possible existence of a superconducting phase in such systems and its properties. Forthis purpose, the question of the statistics of the mobile holes (or ?holons?) shall be ad-dressed first. Such issues are studied in details in this work for generic doped QDM definedon the most common two-dimensional lattices (square, triangular, honeycomb, kagome,...)and involving general resonant loops. We prove a general ?statistical transmutation? sym-metry of such doped QDM by using composite operators of dimers and holes. This exacttransformation enables to define duality equivalence classes (or families) of doped QDM,and provides the analytic framework to analyze dynamical statistical transmutations. Wediscuss various possible superconducting phases of the system. In particular, the possibilityof an exotic superconducting phase originating from the condensation of (bosonic) charge-e holons is examined. A numerical study of such a superconducting phase is presented inthe case of the triangular lattice, by introducing a novel gauge-invariant holon Green?sfunction. We also make the connection with a Bose-Hubbard model on the kagome latticewhich gives rise, as an effective model in the limit of strong interactions, to a doped QDMon the triangular lattice.