Our paper, discussed in some detail here:
https://mkschmidtphysics.blog/2022/12/01/new-prepring-on-the-intensity-correlations-in-ultra-strongly-coupled-systems/
is now published as Phys. Rev. Research 5, 043213 (2023). You can find a free version at arXiv:2306.15152 (2023) or contact me.
Mikołaj K. Schmidt 