Spectroscopic evidence of the existence of substantial Ca 3d derived states at the Fermi level in the Ca-intercalated graphite superconductor CaC6
H. Okazaki, R. Yoshida, K. Iwai, K. Noami, T. Muro, T. Nakamura, T. Wakita, Y. Muraoka, M. Hirai, F. Tomioka, Y. Takano, A. Takenaka, M. Toyoda, T. Oguchi, T. Yokoya.