Quasi-classical localized states in the 2D ferrimagnet

Yury Panov,Alexander Moskvin,N Perov,A Semisalova

doi:10.1051/epjconf/201818511012

Abstract

We consider highly anisotropic 2D quantum s = 1/2 (pseudo)magnetic system which is equivalent to the frequently used system of charged hard-core bosons on a square lattice. In the continuous quasi-classical approximation, the types of localized excitations are determined by asymptotic analysis and compared with numerical results. Depending on the homogeneous ground state, the excitations are the ferro and antiferro type vortices, the skyrmion-like topological excitations or linear domain walls.

Highlights

We construct a continuous two-sublattice approximation for the 2D system of charged hard-core bosons, that is equivalent to the highly anisotropic s = 1/2 2D magnets with a constant magnetization
We consider the asymptotic behavior of localized solutions which converge to homogeneous solutions at infinity and do find their phase diagram
The results are compared with numerical calculations of the ground-state energy in the quasi-classical approximation

Summary

Introduction

Quasi-classical continuous description of the 2D magnetic systems reveals their striking features, namely, the collective localized inhomogeneous states with nontrivial topology and finite excitation energy. These include topological solitons [5, 6], magnon drops [7], in- and out-of-plane vortex-antivortex pairs [8], and various spiral solutions [9,10,11]. These solutions have been obtained for the isotropic and anisotropic ferromagnet. The results are compared with numerical calculations of the ground-state energy in the quasi-classical approximation

The model

The asymptotic behavior of localized solutions

Discussion