Population Oscillations and Ubiquitous Coherences in multilevel quantum systems driven by incoherent radiation

TL;DR

This paper demonstrates that incoherent radiation can induce population oscillations and coherences in multilevel quantum systems with four or more states, revealing new quantum interference phenomena.

Contribution

It shows that geometric constraints ensure noise-induced coherences in complex systems and links these to observable population oscillations, advancing understanding of quantum dynamics under incoherent excitation.

Findings

Noise-induced coherences occur in systems with four or more energy states.

Population oscillations result from quantum interference via coherence transfer.

Experimental detection of noise-induced coherence dynamics is facilitated.

Abstract

We consider incoherent excitation of multilevel quantum systems, e.g. molecules with multiple vibronic states. We show that (1) the geometric constraints of the matter-field coupling operator guarantee that noise-induced coherences will be generated in all systems with four or more energy eigenstates and (2) noise-induced coherences can lead to population oscillations due to quantum interference via coherence transfer between pairs of states in the ground and excited manifolds. Our findings facilitate the experimental detection of noise-induced coherent dynamics in complex quantum systems.