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Title: An effective field theory of magneto-elasticity
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 theLandau-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-elasticphenomena from first principles. As an example we use this theory to calculate the leading order contribution to the magnon decay width dueto its the decay into phonons.  more » « less
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SciPost Physics
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National Science Foundation
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