Effect of impurities on stability of the skyrmion phase in a frustrated Heisenberg antiferromagnet

Abstract

We employ a hybrid Monte Carlo simulation implemented on GPU to study the effect of nonmagnetic impurities in a frustrated Heisenberg antiferromagnetic (AFM) model on a triangular lattice with Dzyaloshinskii-Moriya interaction in the presence of the external magnetic field. We focus on the skyrmion lattice phase (SkX), which in the pure model is known to be stabilized in a quite wide temperature-field window. We aim to confront the effect of impurities on the SkX phase in the present frustrated AFM model with that in the nonfrustrated ferromagnetic counterpart as well as to consider more realistic conditions in the proposed experimental realizations of the present model. We show, that up to a fairly large concentration of the impurities, p ~35%, the SkX phase can survive albeit in somewhat distorted form. Distortion of the SkX phase due to formation of bimerons, reported in the ferromagnetic model, was not observed in the present case.