Correction to: Nature Communications https://doi.org/10.1038/s41467-017-02447-7, published online 03 January 2018

The original version of this Article contained an error in Fig. 3. The scale bars in Figs 3c and d were incorrectly labelled as 50 μA. In the correct version, the scale bars are labelled as 0.5 μA. This has now been corrected in both the PDF and HTML versions of the Article.