1. Physics Department, University of Calabria, Rende 87036, CS, Italy
2. Consiglio Nazionale delle Ricerche - Istituto di Nanotecnologia (CNR-Nanotec), Rende 87036, CS, Italy
3. Physics Department, University of Florence, Sesto Fiorentino 50019, FI, Italy
4. European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino 50019, FI, Italy
5. Istituto Nazionale di Ricerca Metrologica (INRiM), Torino 10135, Italy
6. CNR-ICAR - Institute for High Performance and Networking, Rende 87036, CS, Italy
7. Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China
8. Environmental Engineering Department, University of Calabria, Rende 87036, CS, Italy
9. CNR-INO - National Institute of Optics, Sesto Fiorentino 50019, FI, Italy