Scientific Reports 7: Article number: 44763; published online: 16 March 2017; updated: 15 June 2017.

In this Article, an affiliation for Jordi Arbiol was omitted. The correct affiliations for Jordi Arbiol are listed below:

Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, 08193 Barcelona, Catalonia, Spain.

ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Catalonia, Spain.