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From the Hubbard Model to a Systematic Low-Energy Effective Field Theory for Magnons and Holes in an Antiferromagnet

C. Brügger·F. Kämpfer·M. Moser·M. Pepe·U. -J. Wiese
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Abstract

The low-energy physics of antiferromagnets is governed by their Goldstone bosons -- the magnons -- and it is described by a low-energy effective field theory. In analogy to baryon chiral perturbation theory, we construct the effective field theory for magnons and holes in an antiferromagnet. It is a systematic low-energy expansion based on symmetry considerations and on the fact that the holes are located in pockets centered at k=(pi/2a,\pm pi/2a). Even though the symmetries are extracted from the Hubbard model, the effective theory is universal and makes model-independent predictions about the dynamical mechanisms in the antiferromagnetic phase. The low-energy effective theory has been used to investigate one-magnon exchange which leads to a d-wave-shaped bound state of holes.

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C. Brügger, F. Kämpfer, M. Moser, M. Pepe, U. -J. Wiese. 2006-06-26. From the Hubbard Model to a Systematic Low-Energy Effective Field Theory for Magnons and Holes in an Antiferromagnet. https://doi.org/10.1016/j.physc.2007.03.241

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