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Effective action approach to a bi-layer frustrated antiferromagnet

A. Dotsenko
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Abstract

A bi-layer quantum frustrated antiferromagnet is studied using an effective action approach. The action derived from the microscopical Hamiltonian has the form of the O(3) non-linear sigma model. It is solved in the mean field approximation with the ultraviolet cut off chosen to fit numerical results. The obtained phase diagram displays a decrease in the critical value of interlayer coupling with increase of in-plane frustration. The critical point for a single-layer frustrated antiferromagnet (the J1-J2 model) is estimated to be J_{2c} = 0.19 J_1.

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A. Dotsenko. 1995-05-05. Effective action approach to a bi-layer frustrated antiferromagnet. https://doi.org/10.1103/physrevb.52.9170

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