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arXiv · 1903.03655

Oscillations in electron transport caused by multiple resonances in a quantum dot-QED system in the steady-state regime

Nzar Rauf Abdullah·Chi-Shung Tang·Andrei Manolescu·Vidar Gudmundsson
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Abstract

We model the electron transport current as the photon energy is swept through several resonances of a multi-level quantum dot, embedded in a short quantum wire, coupled to photon cavity. We use a Markovian quantum master equation appropriate for the long-time evolution and include the electron-electron and both the para- and the diamagnetic electron-photon interactions via diagonalization in a truncated many-body Fock space. Tuning the photon energy, several anti-crossings caused by Rabi-splitting in the energy spectrum of the quantum dot system are found. The strength of the Rabi-splittings and the photon-exchange between the resonant states depend on the polarization of the cavity photon field. We observe oscillations of the charge in the system and several resonant transport current peaks for the photon energies corresponding to the resonances in the steady-state regime.

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Nzar Rauf Abdullah, Chi-Shung Tang, Andrei Manolescu, Vidar Gudmundsson. 2019-03-08. Oscillations in electron transport caused by multiple resonances in a quantum dot-QED system in the steady-state regime. https://doi.org/10.1016/j.physe.2020.114221

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