**Author details**

Juan Antonio Delgado-Notario1 \*, Vito Clericò1 , Kristel Fobelets2 , Jesús Enrique Velázquez-Pérez1 and Yahya Moubarak Meziani1

\*Address all correspondence to: juanandn@usal.es

1 USAL NanoLab, University of Salamanca, Salamanca, Spain

2 Department of Electrical and Electronic Engineering, Imperial College, South Kensington Campus, London, UK
