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Quantum critical points with the Coulomb interaction and the dynamical exponent: when and why z=1

Igor F. Herbut
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Abstract

A general scenario that leads to Coulomb quantum criticality with the dynamical critical exponent z=1 is proposed. I point out that the long-range Coulomb interaction and quenched disorder have competing effects on z, and that the balance between the two may lead to charged quantum critical points at which z=1 exactly. This is illustrated with the calculation for the Josephson junction array Hamiltonian in dimensions D=3-ε. Precisely in D=3, however, the above simple result breaks down, and z>1. Relation to other theoretical studies is discussed.

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Igor F. Herbut. 2001-09-06. Quantum critical points with the Coulomb interaction and the dynamical exponent: when and why z=1. https://doi.org/10.1103/physrevlett.87.137004

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