title: Kosterlitz-Thouless transitions and phase diagrams of the interacting monomer-dimer model on a checkerboard lattice.
abstract: Using the tensor network approach, we investigate the monomer-dimer models on a checkerboard lattice, in which there are interactions (with strength v) between the parallel dimers on half of the plaquettes. For the fully packed interacting dimer model, we observe a Kosterlitz-Thouless (KT) transition between the low-temperature symmetry breaking and the high-temperature critical phases; for the doped monomer-dimer case with finite chemical potential μ, we also find an order-disorder phase transition which is of second order instead. We use the boundary matrix product state approach to detect the KT and second-order phase transitions and obtain the phase diagrams v-T and μ-T. Moreover, for the noninteracting monomer-dimer model (setting μ=ν=0), we get an extraordinarily accurate determination of the free energy per site (negative of the monomer-dimer constant h_{2}) as f=-0.662798972833746 with the dimer density n=0.638123109228547, both of 15 correct digits.
authors.affiliation: Department of Physics, Beihang University, Beijing 100191, China.
authors.forename: Sazi
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Physics, Beihang University, Beijing 100191, China and Physics Department, Arnold Sommerfeld Center for Theoretical Physics, and Center for NanoScience, Ludwig-Maximilians-Universität, 80333 Munich, Germany.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Physics, Beihang University, Beijing 100191, China and Key Laboratory of Micro-nano Measurement-Manipulation and Physics (Ministry of Education), Beihang University, Beijing 100191, China.
authors.forename: Ziyu
authors.initials: Z
authors.lastname: Chen