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arXiv · 1909.03630

Back-action effects in cavity-coupled quantum conductors

Valeriu Moldoveanu·Ion Viorel Dinu·Andrei Manolescu·Vidar Gudmundsson
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Abstract

We study the electronic transport through a pair of distant nanosystems ($S_a$ and $S_b$) embedded in a single-mode cavity. Each system is connected to source and drain particle reservoirs and the electron-photon coupling is described by the Tavis-Cummings model. The generalized master equation approach provides the reduced density operator of the double-system in the dressed-states basis. It is shown that the photon-mediated coupling between the two subsystems leaves a signature on their transient and steady-state currents. In particular, a suitable bias applied on subsystem $S_b$ induces a photon-assisted current in the other subsystem $S_a$ which is otherwise in the Coulomb blockade. We also predict that a transient current passing through one subsystem triggers a charge transfer between the optically active levels of the second subsystem even if the latter is not connected to the leads. As a result of back-action, the transient current through the open system develops Rabi oscillations (ROs) whose period depends on the initial state of the closed system.

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Valeriu Moldoveanu, Ion Viorel Dinu, Andrei Manolescu, Vidar Gudmundsson. 2019-09-09. Back-action effects in cavity-coupled quantum conductors. https://doi.org/10.1103/physrevb.100.125416

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