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Effective Field Theory Approach to Ferromagnets and Antiferromagnets in Crystaline Solids

J. M. Roman·J. Soto
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Abstract

We present a systematic construction of effective lagrangians for the low energy and momentum region of ferromagnetic and antiferromagnetic spin waves in crystalline solids. We fully exploit the spontaneous symmetry breaking pattern $SU(2)\to U(1)$, the fact that spin waves are its associated Goldstone modes, the crystallographic space group and time reversal symmetries. We show how to include explicit SU(2) breaking terms due to spin-orbit and magnetic dipole interactions. The coupling to electromagnetic fields is also discussed in detail. For definiteness we work with the space group $R\bar 3 c$ and present our results to next to leading order.

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J. M. Roman, J. Soto. 1999-06-18. Effective Field Theory Approach to Ferromagnets and Antiferromagnets in Crystaline Solids. https://doi.org/10.1142/s0217979299000655

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