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Strong Electron Tunneling through Mesoscopic Metallic Grains

D. S. Golubev·Jürgen König·Herbert Schoeller·Gerd Schön·A. D. Zaikin
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Abstract

We describe electron transport through small metallic grains with Coulomb blockade effects beyond the perturbative regime. For this purpose we study the real-time evolution of the reduced density matrix of the system. In the first part of the paper we present a diagrammatic expansion for not too high junction conductance, $h/4π^2e^2 R_t \lesssim 1$, in a basis of charge states. Quantum fluctuations renormalize system parameters and lead to finite lifetime broadening in the gate-voltage dependent differential conductance. We derive analytic results for the spectral density and the conductance in the limit where only two charge states play a role. In the second part of the paper we consider junctions with large conductance, $h/4e^2 R_t \gtrsim 1$. In this case contributions from all charge states, which broaden and overlap, become important. We analyze the problem in a quasiclassical approximation. The two complementary approaches cover the essential features of electron tunneling for all parameters.

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D. S. Golubev, Jürgen König, Herbert Schoeller, Gerd Schön, A. D. Zaikin. 1997-02-11. Strong Electron Tunneling through Mesoscopic Metallic Grains. https://doi.org/10.1103/physrevb.56.15782

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