1 Física Teòrica: Informació i Fenòmens Quàntics, Departament de Física, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain. matteo.rosati@uab.cat.
2 NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, 56127, Pisa, Italy. matteo.rosati@uab.cat.
3 NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, 56127, Pisa, Italy.
The original version of this Article contained an error in Equation (40). The numerator of the fraction inside the logarithm was missing an overall minus sign. This has been corrected in the PDF and HTML versions of the Article.