A Unified Theory of Magnetoelastic Effects in B20 compounds

Yangfan Hu, Biao Wang

Published 2016-04-11Version 1

A novel functional of magnetoelastic effects for B20 compounds is proposed, incorporating higher order terms obtained through group theoretical analysis. An extended micromagnetic model determining the coupled elastic and magnetization field in chiral magnets at given temperature and magnetic field is then developed. Through the theory, we are able to quantitatively explain various kinds of experimental results related to the magnetic, elastic and magnetoelastic properties of MnSi, including experiments of the temperature-magnetic field phase diagram, the magnetostriction, and the variation of elastic coefficients with magnetic field. Our model is vital for conducting any numerical simulation concerning the elastic and magnetoelastic behavior of chiral magnets, and for uncovering the nature of the emergent elastic property of magnetic skyrmions.