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arXiv · 2112.13873

An Effective Field Theory of Magneto-Elasticity

Shashin Pavaskar·Riccardo Penco·Ira Z. Rothstein
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Abstract

We utilize the coset construction to derive the effective field theory of magnon-phonon interactions in (anti)-ferromagnetic and ferrimagnetic insulating materials. The action is used to calculate the equations of motion which generalize the Landau-Lifshitz and stress equations to allow for magneto-acoustic couplings to all orders in the fields at lowest order in the derivative expansion. We also include the symmetry breaking effects due to Zeeman, and Dzyaloshinsky-Moriya interactions. This effective theory is a toolbox for the study of magneto-elastic phenomena from first principles. As an example we use this theory to calculate the leading order contribution to the magnon decay width due to its the decay into phonons.

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Shashin Pavaskar, Riccardo Penco, Ira Z. Rothstein. 2021-12-27. An Effective Field Theory of Magneto-Elasticity. https://doi.org/10.21468/scipostphys.12.5.155

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