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DOE OSTI · 1976825

Topological order in Mott insulators

Trivedi, Nandini
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Abstract

Here in this commemorative issue for Phil Anderson, I reproduce parts of a joint unpublished paper that first got me thinking about topological order in Mott insulators. With Phil, we explored aspects of the momentum distribution function and the non-classical rotational inertia in the Bose Hubbard model close to the quantum phase transition. My interest on this question continued, and later in the article I take up the question of topological order in the Kitaev Mott insulator on the honeycomb lattice with bond-dependent interactions in a finite magnetic field. Kitaev obtained the exact solution for zero field that demonstrated an exotic Z 2 quantum spin liquid phase with topological order. In a finite magnetic field, we discovered a new intermediate U(1) gapless quantum spin liquid phase, sandwiched between the known gapped Kitaev spin liquid and a polarized phase, that harbors fractionalized neutral fermionic excitations, dubbed spinons, that remarkably form a Fermi surface in a Mott insulator.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSHubbard modelMott insulatorentanglementquantum matterquantum spin liquidstrong correlations

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Trivedi, Nandini. 2021-10-01. Topological order in Mott insulators. https://doi.org/10.1016/j.aop.2021.168636

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