Yang-Baxter Integrable Dimers on a Strip [article]

Paul A. Pearce, Jørgen Rasmussen, Alessandra Vittorini-Orgeas
2019 arXiv   pre-print
The dimer model on a strip is considered as a Yang-Baxter six vertex model at the free-fermion point with crossing parameter λ=π2 and quantum group invariant boundary conditions. A one-to-many mapping of vertex onto dimer configurations allows for the solution of the free-fermion model to be applied to the anisotropic dimer model on a square lattice where the dimers are rotated by 45 compared to their usual orientation. In a suitable gauge, the dimer model is described by the Temperley-Lieb
more » ... bra with loop fugacity β=2cosλ=0. It follows that the model is exactly solvable in geometries of arbitrary finite size. We establish and solve transfer matrix inversion identities on the strip with arbitrary finite width N. In the continuum scaling limit, in sectors with magnetization S_z, we obtain the conformal weights Δ_s=((2-s)^2-1)/8 where s=|S_z|+1=1,2,3,.... We further show that the corresponding finitized characters _s^(N)(q) decompose into sums of q-Narayana numbers or, equivalently, skew q-binomials. In the particle representation, the local face tile operators give a representation of the fermion algebra and the fermion particle trajectories play the role of nonlocal degrees of freedom. We argue that, in the continuum scaling limit, there exist nontrivial Jordan blocks of rank 2 in the Virasoro dilatation operator L_0. This confirms that, with quantum group invariant boundary conditions, the dimer model gives rise to a logarithmic conformal field theory with central charge c=-2, minimal conformal weight Δ_min=-1/8 and effective central charge c_eff=1.Our analysis of the structure of the ensuing rank 2 modules indicates that the familiar staggered c=-2 modules appear as submodules.
arXiv:1907.07610v2 fatcat:gqwuqfvatrg3nbfpkhdkqqqhhq