Correction to: Nature Materials https://doi.org/10.1038/s41563-021-01011-5, published online 20 May 2021.

In the version of this Letter initially published online, there was an error in the Acknowledgements section. Specifically, the first sentence, acknowledging help from scientists at the Australian Nuclear Science and Technology Organization, now reading “We wish to thank H. W. Kui for helpful discussions, Z. G. Ding for first-principles calculations and E. P. Gilbert for SANS measurements at QUOKKA in ANSTO, Australia” showed the name of E. P. Gilbert as “G. Elliott.” The correction has been made to the online version of the paper.