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Coulomb Blockade and Insulator-to-Metal Quantum Phase Transition

Dmitri S. Golubev·Andrei D. Zaikin
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Abstract

We analyze an interplay between Coulomb blockade and quantum fluctuations in a coherent conductor (with dimensionless conductance $g \gtrsim 1$) attached to an Ohmic shunt. We demonstrate that at T=0 the system can be either an insulator or a metal depending on whether its total resistance is larger or smaller than $h/e^2\approx 25.8$ k$Ω$. In a metallic phase the Coulomb gap is fully suppressed by quantum fluctuations. We briefly discuss possible relation of this effect to recent experiments indicating the presence of a metal-insulator phase transition in 2d disordered systems.

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Dmitri S. Golubev, Andrei D. Zaikin. 2001-04-17. Coulomb Blockade and Insulator-to-Metal Quantum Phase Transition. https://doi.org/10.1209/epl%2Fi2002-00327-4

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