The first angle-resolved photo-emission spectroscopy results from MgB2 single crystals were reported. Along the ΓK and ΓM directions, 2 distinct dispersive features were observed approaching the Fermi energy. These could be attributed to the theoretically predicted σ(B 2px,y) and π (B 2pz) bands. In addition, a small parabolic-like band was detected around the Γ point, which could be attributed to a surface-derived state. The overall agreement between these results and band calculations suggested that the electronic structure of MgB2 was of a conventional nature; thus implying that electron correlations were weak and probably of little importance to superconductivity in this system.

Electronic Structure of MgB2 from Angle-Resolved Photoemission Spectroscopy. H.Uchiyama, K.M.Shen, S.Lee, A.Damascelli, D.H.Lu, D.L.Feng, Z.X.Shen, S.Tajima: Physical Review Letters, 2002, 88[15], 157002 (3pp)