Two photons everywhere. E. Zubizarreta Casalengua, F. P. Laussy and E. del Valle in Phil. Trans. R. Soc. A 382:20230315 (2024). 
What the paper says!?
This paper explains most of the two-photon structure of resonance fluorescence, in particular, it clarifies for the first time the nature of the circle of antibunching that appears in the two-photon correlation spectrum, which had hitherto remained mysterious since their first report.[1] The text is written self-consistently, so it requires no acquaintance with our earlier works, in particular the theory of frequency-resolved photon correlations[2] and the theory of interfering quantum fields,[3]—whose union actually accounts for the said circles—are both introduced from scratch.
I wrote a long series (four part) of tweets to break down the content of this paper:
There you can see things one cannot find anywhere else, like Dalibard on steroids [1][2]:
References
- ↑ Two-photon spectra of quantum emitters. A. González-Tudela, F. P. Laussy, C. Tejedor, M. J Hartmann and E. del Valle in New J. Phys. 15:033036 (2013).
- ↑ Theory of Frequency-Filtered and Time-Resolved $N$-Photon Correlations. E. del Valle, A. González-Tudela, F. P. Laussy, C. Tejedor and M. J. Hartmann in Phys. Rev. Lett. 109:183601 (2012).
- ↑ Conventional and Unconventional Photon statistics. E. Zubizarreta Casalengua, J. C. López Carreño, F. P. Laussy and E. del Valle in Laser Photon. Rev. 14:1900279 (2020).