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arXiv · 1703.00803

Cavity-enhanced transport of charge

David Hagenmüller·Johannes Schachenmayer·Stefan Schütz·Claudiu Genes·Guido Pupillo
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Abstract

We theoretically investigate charge transport through electronic bands of a mesoscopic one-dimensional system, where inter-band transitions are coupled to a confined cavity mode, initially prepared close to its vacuum. This coupling leads to light-matter hybridization where the dressed fermionic bands interact via absorption and emission of dressed cavity-photons. Using a self-consistent non-equilibrium Green's function method, we compute electronic transmissions and cavity photon spectra and demonstrate how light-matter coupling can lead to an enhancement of charge conductivity in the steady-state. We find that depending on cavity loss rate, electronic bandwidth, and coupling strength, the dynamics involves either an individual or a collective response of Bloch states, and explain how this affects the current enhancement. We show that the charge conductivity enhancement can reach orders of magnitudes under experimentally relevant conditions.

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David Hagenmüller, Johannes Schachenmayer, Stefan Schütz, Claudiu Genes, Guido Pupillo. 2017-07-01. Cavity-enhanced transport of charge. https://doi.org/10.1103/physrevlett.119.223601

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