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Multi-particle effects in non-equilibrium electron tunnelling and field emission

Andrei Komnik·Alexander O. Gogolin
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Abstract

We investigate energy resolved electric current from various correlated host materials under out-of-equilibrium conditions. We find that, due to a combined effect of electron-electron interactions, non-equilibrium and multi-particle tunnelling, the energy resolved current is finite even above the Fermi edge of the host material. In most cases, the current density possesses a singularity at the Fermi level revealing novel manifestations of correlation effects in electron tunnelling. By means of the Keldysh non-equilibrium technique, the current density is calculated for one-dimensional interacting electron systems and for two-dimensional systems, both in the pure limit and in the presence of disorder. We then specialise to the field emission and provide a comprehensive theoretical study of this effect in carbon nanotubes.

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Andrei Komnik, Alexander O. Gogolin. 2002-03-01. Multi-particle effects in non-equilibrium electron tunnelling and field emission. https://doi.org/10.1103/physrevb.66.035407

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