Correction to: Nature Photonics, published online 1 April 2019.

In the version of this Article originally published online, in Fig. 1b, the chemical structures of phenylethylamine and formamidine had incorrect numbers of hydrogen atoms. In Fig. 4a, in the legend, the black and red lines were reversed; the black line should have been labelled ‘Without PEAI fitting’ and the red line ‘With PEAI fitting’. These errors have now been corrected in all versions.

Fig. 1b
figure 1

Original and corrected.