Helimagnetic thin films: surface reconstruction, surface spin-waves and magnetization

TL;DR

This study investigates the quantum properties of helimagnetic thin films, revealing non-uniform spin configurations, surface-localized spin-wave modes, and quantum fluctuation effects on magnetization at various temperatures.

Contribution

It provides an exact determination of spin configurations and analyzes surface effects and quantum fluctuations in helimagnetic thin films using Green's function methods.

Findings

Existence of surface-localized spin-wave modes

Quantum fluctuations induce spin contractions at zero temperature

Layer magnetizations cross over at low temperatures

Abstract

Quantum properties of a helimagnetic thin film of simple cubic lattice with Heisenberg spin model are studied using the Green's function method. We find that the spin configuration across the film is strongly non uniform. Using the exactly determined spin configuration we calculate the spin-wave spectrum and the layer magnetizations as functions of temperature T. We show the existence of surface-localized modes which strongly affect the surface magnetization. We also show that quantum fluctuations cause interesting spin contractions at T = 0 and give rise to a cross-over between layer magnetizations at low T .