Unconventional state with two coexisting long-range orders for frustrated Heisenberg model at quantum phase transition

A. V. Mikheyenkov; N. A. Kozlov; A. F. Barabanov

doi:10.1016/j.physleta.2010.01.003

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arXiv · 0912.4008

Unconventional state with two coexisting long-range orders for frustrated Heisenberg model at quantum phase transition

A. V. Mikheyenkov·N. A. Kozlov·A. F. Barabanov

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Abstract

For the frustrated two-dimensional $S=1/2$ antiferromagnetic Heisenberg model close to quantum phase transition we consider the singlet ground states retaining both translational and SU(2) symmetry. Besides usually discussed checkerboard, spin-liquid and stripe states an unconventional state with two coexisting long-range orders appears to be possible at sufficiently large damping of spin excitations. The problem is treated in the frames of self-consistent spherically symmetric approach.

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A. V. Mikheyenkov, N. A. Kozlov, A. F. Barabanov. 2009-12-20. Unconventional state with two coexisting long-range orders for frustrated Heisenberg model at quantum phase transition. https://doi.org/10.1016/j.physleta.2010.01.003

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