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Quantum Dots with Disorder and Interactions: A Solvable Large-g Limit

Ganpathy Murthy·R. Shankar
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Abstract

We show that problem of interacting electrons in a quantum dot with chaotic boundary conditions is solvable in the large-g limit, where g is the dimensionless conductance of the dot. The critical point of the $g=\infty$ theory (whose location and exponent are known exactly) that separates strong and weak-coupling phases also controls a wider fan-shaped region in the coupling-1/g plane, just as a quantum critical point controls the fan in at T>0. The weak-coupling phase is governed by the Universal Hamiltonian and the strong-coupling phase is a disordered version of the Pomeranchuk transition in a clean Fermi liquid. Predictions are made in the various regimes for the Coulomb Blockade peak spacing distributions and Fock-space delocalization (reflected in the quasiparticle width and ground state wavefunction).

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Ganpathy Murthy, R. Shankar. 2002-09-05. Quantum Dots with Disorder and Interactions: A Solvable Large-g Limit. https://doi.org/10.1103/physrevlett.90.066801

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