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arXiv · 1812.04502

Environmental non-additivity and Franck-Condon physics in non-equilibrium quantum systems

Henry Maguire·Jake Iles-Smith·Ahsan Nazir
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Abstract

We show that for a quantum system coupled to both vibrational and electromagnetic environments, enforcing additivity of their combined influences results in non-equilibrium dynamics that does not respect the Franck-Condon principle. We overcome this shortcoming by employing a collective coordinate representation of the vibrational environment, which permits the derivation of a non-additive master equation. When applied to a two-level emitter our treatment predicts decreasing photon emission rates with increasing vibrational coupling, consistent with Franck-Condon physics. In contrast, the additive approximation predicts the emission rate to be completely insensitive to vibrations. We find that non-additivity also plays a key role in the stationary non-equilibrium model behaviour, enabling two-level population inversion under incoherent electromagnetic excitation.

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Henry Maguire, Jake Iles-Smith, Ahsan Nazir. 2018-12-11. Environmental non-additivity and Franck-Condon physics in non-equilibrium quantum systems. https://doi.org/10.1103/physrevlett.123.093601

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