Contrasting pseudo-criticality in the classical two-dimensional Heisenberg and ${\mathrm{RP}}^2$ models: zero-temperature phase transition versus finite-temperature crossover

Lander Burgelman, Lukas Devos, Bram Vanhecke +2

Tensor-network methods are used to perform a comparative study of the two-dimensional classical Heisenberg and ${\mathrm{RP}}^2$ models. We demonstrate that uniform matrix product st…