1. European Laboratory for Non-linear Spectroscopy, via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
2. Department of Biomedical, Experimental, and Clinical Sciences “Mario Serio”, University of Florence, viale Morgagni 50, 50143 Florence, Italy
3. Istituto Nazionale di Ricerca Metrologica (INRiM), strada delle Cacce 91, 10135 Turin, Italy
4. Department of Physics and Astronomy, University of Florence, via Sansone 1, 50019 Sesto Fiorentino, Italy
5. Department of Chemistry “Ugo Schiff”, University of Florence, via della Lastruccia 3−13, 50019 Sesto Fiorentino, Italy