Single molecule photon counting statistics for quantum mechanical chromophore dynamics

TL;DR

This paper develops a quantum mechanical extension of photon counting statistics calculations, enabling analysis of spectrally resolved photon emissions influenced by quantum coherence, surpassing traditional stochastic models.

Contribution

It introduces a method to compute photon statistics for multi-level quantum systems, allowing for spectral resolution and quantum coherence effects analysis.

Findings

Method captures quantum coherence in photon statistics

Spectrally resolved photon counting reveals more system dynamics

Differences identified between quantum models and stochastic approximations

Abstract

We extend the generating function technique for calculation of single molecule photon emission statistics [Y. Zheng and F. L. H. Brown, Phys. Rev. Lett., 90,238305 (2003)] to systems governed by multi-level quantum dynamics. This opens up the possibility to study phenomena that are outside the realm of purely stochastic and mixed quantum-stochastic models. In particular, the present methodology allows for calculation of photon statistics that are spectrally resolved and subject to quantum coherence. Several model calculations illustrate the generality of the technique and highlight quantitative and qualitative differences between quantum mechanical models and related stochastic approximations. Calculations suggest that studying photon statistics as a function of photon frequency has the potential to reveal more about system dynamics than the usual broadband detection schemes.