Correction to: Nature Physics https://doi.org/10.1038/s41567-022-01720-x, published online 1 September 2022.

In the version of this article initially published, there was a citation error in the sixth paragraph, now reading in part, “The calculation of the two-photon response was obtained following an approach as outlined in ref. 43,” where ref. 43 (Ramos, T. & García-Ripoll, J. J. Phys. Rev. Lett. 119, 153601 (2017)) replaces the originally cited ref. 44 (Houck, M. et al. Phys. Rev. Lett. 124, 16051 (2020)), which has been removed from the reference list. The change has been made to the HTML and PDF versions of the article.