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arXiv · 1902.05580

Phonon-assisted tunnelling in a double quantum dot molecule immersed in a cavity

Vladimir Vargas-Calderón·Herbert Vinck-Posada
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Abstract

The effects caused by phonon-assisted tunnelling (PhAT) in a double quantum dot (QD) molecule immersed in a cavity were studied under the quantum Markovian master equation formalism in order to account for dissipation phenomena. We explain how for higher PhAT rates, a stronger interaction between a QD and the cavity at off-resonance takes place through the resonant interaction of another QD and the cavity, where the QDs interact through tunnelling. A closer look at the system's allowed optical transitions as a function of PhAT rates showed coalescence of the transition energies, leading to a loss of spectroscopic resolution in the photoluminescence (PL) spectrum. This coalescence occurs at several exceptional points, suggesting a quantum dynamical phase transition.

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Vladimir Vargas-Calderón, Herbert Vinck-Posada. 2019-02-14. Phonon-assisted tunnelling in a double quantum dot molecule immersed in a cavity. https://doi.org/10.1016/j.ijleo.2019.02.035

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