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Bosonic Mean Field Theory of the Spiral Phases of Heisenberg Antiferromagnets on a Chain

Sumathi Rao·Diptiman Sen
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Abstract

We develop a novel bosonic mean field theory to describe the spiral phases of a Heisenberg antiferromagnet on a one-dimensional chain, in terms of three bosons at each site. The ground state is disordered and for large values of the spin $S$, two different and exponentially small energy gaps are found. The spin-spin correlation function is computed and is shown to decay exponentially at large distances. Our mean field theory is also shown to be exact in a large-$N$ generalization.

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Sumathi Rao, Diptiman Sen. 1993-01-06. Bosonic Mean Field Theory of the Spiral Phases of Heisenberg Antiferromagnets on a Chain. https://doi.org/10.1103/physrevb.48.12763

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