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Novel quantum criticality due to emergent topological conservation law in high-$T_c$ cuprates

T. K. Kopec
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Abstract

We argue that in strongly correlated electron system collective instanton excitations of the phase field (dual to the charge) arise with a great degree of stability, governed by gauge flux changes by an integer multiple of $2π$. By unraveling consequences of the non-trivial topology of the charge gauge U(1) group, we found that the pinning of $μ$ and the zero-temperature divergence of charge compressibility $κ\sim\partial n_e/\partialμ$ defines novel "hidden" quantum criticality on verge of the Mott transition governed by the protectorate of stable topological numbers rather than Landau paradigm of the symmetry breaking.

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T. K. Kopec. 2006-05-18. Novel quantum criticality due to emergent topological conservation law in high-$T_c$ cuprates. https://doi.org/10.1016/j.physb.2006.01.262

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