Correction to: Communications Materials https://doi.org/10.1038/s43246-021-00166-7, published online 9 June 2021.

An error was introduced into one sentence of this Article during typesetting.

“the final values of n = 0.226 and k = 0.311 obtained for a wavenumber of 1058 cm−1” has now been replaced with “the final values of n = 1.226 and k = 0.311 obtained for a wavenumber of 1058 cm−1”.

This error has been corrected in both the HTML and PDF versions of the Article.