Magnetization process in the classical Heisenberg model on the Shastry-Sutherland lattice

Abstract

We investigate classical Heisenberg spins on the Shastry-Sutherland lattice and under an external magnetic field. A detailed study is carried out both analytically and numerically by means of classical Monte Carlo simulations. Magnetization pseudoplateaus are observed around 1/3 of the saturation magnetization for a range of values of the magnetic couplings. We show that the existence of the pseudoplateaus is due to an entropic selection of a particular collinear state. A phase diagram that shows the domains of existence of those pseudoplateaus in the $(h,T)$ plane is obtained.