# Pure dephasing vs. Phonon mediated off-resonant coupling in a quantum-dot-cavity system

## TL;DR

This paper challenges the use of pure dephasing to explain quantum dot cavity experiments and proposes phonon-mediated coupling as a more accurate mechanism, successfully explaining experimental data without artificial assumptions.

## Contribution

It introduces a phonon-mediated coupling model that replaces pure dephasing in explaining quantum dot cavity phenomena, aligning theory with recent experimental results.

## Key findings

- Phonon-mediated coupling explains emission spectra without pure dephasing.
- The model accounts for photon correlation features previously unexplained.
- Results suggest new directions for experimental verification.

## Abstract

Pure dephasing is widely used in the literature to explain experimental observations on quantum dots in cavities. In many cases, its use is not enough and extra terms need to be "fictitiously" added to accomplish with the observed data as it is the case of cavity pumping of an unknown source. Here we controvert the validity of the pure dephasing mechanism as a source of decoherence and present a theoretical study based on the phonon-mediated coupling that can explain the emission spectrum and photon auto- and cross-correlation results in recent experiments without the need of any artificial assumptions. We also demonstrated that the phonon-mediated coupling accounts for unexplained features recently reported in measurements of photon auto- and cross-correlation functions. Our work illuminates many of the debates in this field and opens up new possibilities for experimental verification and theoretical predictions.