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Fractionalization in Spin Liquid Mott Insulators: Vison Wavefunctions and Gaps

Arun Paramekanti·Mohit Randeria·Nandini Trivedi
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Abstract

We study fractionalization in a spin-liquid Mott insulator defined by a Gutzwiller projected BCS state |0> at half-filling. We construct a trial vison (Z2 vortex) state |V> by projecting an hc/2e vortex and determine when it is orthogonal to |0>. Using a combination of analytical arguments and Monte Carlo calculations we show that generically the spin-liquid is Z2 fractionalized. For microscopic parameters appropriate for high Tc cuprates, we estimate that the vison gap Ev << J, consistent with recent experimental bounds, due to proximity to the bipartite symmetric point where Ev = 0.

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Arun Paramekanti, Mohit Randeria, Nandini Trivedi. 2003-07-16. Fractionalization in Spin Liquid Mott Insulators: Vison Wavefunctions and Gaps. https://doi.org/10.1103/physrevb.71.094421

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