Resonating plaquette phase of a quantum six-vertex model

Olav F. Syljuasen; Sudip Chakravarty

doi:10.1103/physrevlett.96.147004

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Resonating plaquette phase of a quantum six-vertex model

Olav F. Syljuasen·Sudip Chakravarty

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Abstract

The simplest quantum generalization of the six-vertex model describes fluctuations of the order parameter of the d-density wave (DDW), believed to compete with superconductivity in the high-Tc superconductors. The ground state of this model undergoes a first order transition from the DDW phase to a resonating plaquette phase as the quantum fluctuations are increased, which is explored with the help of quantum Monte Carlo simulations and analytic considerations involving the n-vector (n=2) model with cubic anisotropy. In addition to finding a new quantum state, we show that the DDW is robust against a class of quantum fluctuations of its order parameter. The inferred finite temperature phase diagram contains unsuspected multicritical points.

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Olav F. Syljuasen, Sudip Chakravarty. 2006-03-20. Resonating plaquette phase of a quantum six-vertex model. https://doi.org/10.1103/physrevlett.96.147004

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