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arXiv · 2112.02112

Quantum criticality and confinement in weak Mott insulators

Eyal Leviatan·David F. Mross
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Abstract

Electrons undergoing a Mott transition may shed their charge but persist as neutral excitations of a quantum spin liquid (QSL). We introduce concrete two-dimensional models exhibiting this exotic behavior as they transition from superconducting or topological phases into fully charge-localized insulators. We study these Mott transitions and the confinement of neutral fermions at a second transition into a symmetry-broken phase. In the process, we also derive coupled-wire parent Hamiltonians for a non-Abelian QSL and a $\mathbb{Z}_4$ QSL.

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Eyal Leviatan, David F. Mross. 2021-12-03. Quantum criticality and confinement in weak Mott insulators. https://doi.org/10.1103/physrevb.105.l201110

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