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arXiv · 1005.2669

Instability of the chiral d-wave RVB state for the Heisenberg model on triangular lattice and an improvement of the Gutzwiller approximation

Tao Li
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Abstract

Through Variational Monte Carlo simulation we show the d-wave RVB pairing in the Heisenberg model on triangular lattice can be better described in terms of a two component order parameter. The fully gapped chiral d-wave RVB state, which is predicted by the mean field theory to be the unique minimum of variational energy in the two dimensional representation space of d-wave pairing, is found to be actually a local maximum and the true minimum of energy is reached by the non-chiral $d_{xy}$ state with line nodes. We also find that the usual Gutzwiller approximation, which enjoys great success for the square lattice system, fails badly on the triangular lattice as a result of the geometric frustration inherent of the system. An improved version of the Gutzwiiler approximation is proposed and is found to give a much better results than the usual one.

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Tao Li. 2010-05-15. Instability of the chiral d-wave RVB state for the Heisenberg model on triangular lattice and an improvement of the Gutzwiller approximation. https://arxiv.org/abs/1005.2669

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