Correction to: Nature Photonics https://doi.org/10.1038/s41566-020-00745-z, published online 4 January 2021.

In the version of this Letter originally published, the labels of the light-blue and dark-blue lines in the legend of Fig. 1b were the wrong way around; the light-blue line should have been labelled ‘0.5 wt% ν-DABNA: 20 wt% HDT-1:mCBP’ and the dark-blue line should have been labelled ‘0.5 wt% ν-DABNA:mCBP’. This has now been corrected in all versions of the Letter.