Doping quantum dimer models on the square lattice
Résumé
A family of models is proposed to describe the motion of holes in a fluctuating quantum dimer background on the square lattice. Following Castelnovo {\it et al.} [Ann. Phys. (NY) {\bf 318}, 316 (2005)], a generalized Rokhsar-Kivelson Hamiltonian at {\it finite doping} which can be mapped on a {\it doped} interacting classical dimer model is constructed. A simple physical extension of this model is also considered. The two-hole correlation function computed by various (classical and quantum) numerical techniques generically exhibits short-range or long-range algebraic correlations in the solid (columnar) and liquid (critical) phases of the model, respectively. However, we also conjecture the existence of an extended region of the liquid phase where two holes form a bound state and show evidence for hole deconfinement in the staggered dimer phase.