1. Study of the gap and of the pseudogap in La_2-xSr_xCuO₄ as a function of the Sr doping by means of point-contact and tunnel spectroscopy. Main results >>

2. Study of the signature of possible charge-stripe order in underdoped La_2-xSr_xCuO₄ by means of transport measurements. Main results >>

3. Experimental and theoretical study of the symmetry of the order parameter in high-Tc superconductors and its effects on the density of states. Main results >>

4. Experimental and theoretical study of the mechanisms limiting the Josephson critical current in SIS junctions involving HTSC and, in particular, the effect of surface depression of the order parameter at the interfaces. Main results >>

5. Extraction of the electron-phonon spectral function from tunneling measurements by inversion of the Eliashberg Equations. Main results >>

6. Analysis of the structure and the electronic properties of the HTS surfaces by means of scanning microscopy and spectroscopy between 4.2 K and 300 K (STM and AFM). Main results >>

7. Study of the ruthenate-cuprate RuSr₂GdCu₂O₈ by point-contact spectroscopy: investigation of the pairing symmetry. Main results >>

MgB₂ and related compounds

8. Study of polycrystalline MgB₂ by point-contact spectroscopy and break-junction measurements: temperature dependence of the gap, effect of impurities, surface deterioration, Josephson effect. Main results >>

9. Study of the two gaps of MgB₂ as a function of the temperature and of the magnetic field, by means of directional point-contact spectroscopy in single crystals. Main results >>

10. Determination of the upper critical field of MgB₂ by point-contact spectroscopy in single crystals. Main results >>

11. Study of the effect of the magnetic field on the superconducting gap at the surface of MgB₂ single crystals: an evaluation of the intraband scattering. Main results >>

12. Point-contact spectroscopy in ZrB₁₂ single crystals. Main results >>

13. Study of the effect of Al doping on MgB₂ by directional point-contact spectroscopy in single crystals. Main results >>

14. Study of the effect of C doping on MgB₂ by directional point-contact spectroscopy in single crystals. Main results >>

15. Tentative fabrication of weak-link junctions in thin films by means of a AFM-based techniques. Main results >>

Theoretical activities

16. Quantification of the possible effects of the breakdown of Migdal's theorem on the electron-phonon coupling constant, on the critical temperature and on the superconducting gap in various superconductors. Main results >>

17. Calculation of the tunneling density of states of MgB₂ for different tunneling directions by directly solving the two-band Eliashberg equations in the real-axis formulation. Main results >>

18. Theoretical study of the phenomenology of Al-doped magnesium diboride in the framework of s-wave two-band Eliashberg Equations. Main results >>

19. Theoretical study of the phenomenology of field-effect doping in the framework of s-wave finite band Eliashberg theory in the non half filling case. Main results >>