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Nexus between quantum criticality and the chemical potential pinning in high-$T_c$ cuprates

Tadeusz K. Kopec
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Abstract

For strongly correlated electrons the relation between total number of charge carriers $n_e$ and the chemical potential $μ$ reveals for large Coulomb energy the apparently paradoxical pinning of $μ$ within the Mott gap, as observed in high-$T_c$ cuprates. By unravelling consequences of the non-trivial topology of the charge gauge U(1) group and the associated ground state degeneracy we found a close kinship between the pinning of $μ$ and the zero-temperature divergence of the charge compressibility $κ\sim\partial n_e/\partialμ$, which marks a novel quantum criticality governed by topological charges rather than Landau principle of the symmetry breaking.

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Tadeusz K. Kopec. 2005-10-10. Nexus between quantum criticality and the chemical potential pinning in high-$T_c$ cuprates. https://doi.org/10.1103/physrevb.72.060513

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