Quantum critical points with the Coulomb interaction and the dynamical exponent: When and why z=1 - art. no. 137004

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