Correction to: Nature Communications; https://doi.org/10.1038/s41467-018-03696-w; published online 10 April 2018.

The original version of this Article omitted the following from the Acknowledgements:

‘P.B. was funded by the ELI Extreme Light Infrastructure Phase 2 (CZ.02.1.01/0.0/0.0/15008/0000162) from the European Regional Development Fund and the EUCALL project funded from the EU Horizon 2020 research and innovation programme under grant agreement No 654220,’ which replaces the previous ‘P.B. was funded by the ELI Extreme Light Infrastructure Phase 2 (CZ.02.1.01/0.0/0.0/15008/0000162) from the European Regional Development Fund.’

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