Near EF electronic structure of heavily boron-doped superconducting diamond

We have performed soft X-ray angle-resolved photoemission spectroscopy (SXARPES) of a heavily boron-doped superconducting diamond film (Tc=7.2 K) in order to study the electronic structure near the Fermi level (EF). Careful determination of measured momentum space that across Γ point in the Brillouin zone (BZ) and increase of an energy resolution provide further spectroscopic evidence that EF is located at the highly dispersive diamond-like bands, indicating that holes at the top of the diamond-like valence band play an essential role for the conducting properties of the heavily boron-doped superconducting diamond for this boron-doping region (effective carrier concentration of 1.6%). The SXARPES intensities at EF were also mapped out over BZ to obtain experimental Fermi surface sheets and compared with calculations.