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A Phase Glass is a Bose Metal: New Conducting State in 2D

Denis Dalidovich·Philip Phillips
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Abstract

In the quantum rotor model with random exchange interactions having a non-zero mean, three phases, a 1) phase (Bose) glass, 2) superfluid, and 3) Mott insulator, meet at a bi-critical point. We demonstrate that proximity to the bi-critical point and the coupling between the energy landscape and the dissipative degrees of freedom of the phase glass lead to a metallic state at T=0. Consequently, the phase glass is unique in that it represents a concrete example of a metallic state that is mediated by disorder, even in 2D. We propose that the experimentally observed metallic phase which intervenes between the insulator and the superconductor in a wide range of thin films is in actuality a phase glass.

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Denis Dalidovich, Philip Phillips. 2002-06-17. A Phase Glass is a Bose Metal: New Conducting State in 2D. https://doi.org/10.1103/physrevlett.89.027001

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