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arXiv · 1402.4807

Bond order instabilities in a correlated two-dimensional metal

Andrea Allais·Johannes Bauer·Subir Sachdev
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Abstract

Motivated by recent experimental evidence of charge order in the pseudogap phase of cuprates, we perform a variational analysis of charge-neutral, spin-singlet ordering in metals on the square lattice, using a wavefunction with double occupancy projected out. We examine ordering with and without time-reversal symmetry, with arbitrary wavevector and tunable form factor. Depending on parameters, we find d-wave bond density wave ordering with wavevector either parallel to the lattice generators or diagonally oriented, or a ground state which carries a time reversal-breaking pattern of spontaneous currents.

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Andrea Allais, Johannes Bauer, Subir Sachdev. 2014-02-19. Bond order instabilities in a correlated two-dimensional metal. https://doi.org/10.1103/physrevb.90.155114

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