title: Structure and superconductivity of isotope-enriched boron-doped diamond.
abstract: Superconducting boron-doped diamond samples were synthesized with isotopes of10B,11B,13C and12C. We claim the presence of a carbon isotope effect on the superconducting transition temperature, which supports the 'diamond-carbon'-related nature of superconductivity and the importance of the electron-phonon interaction as the mechanism of superconductivity in diamond. Isotope substitution permits us to relate almost all bands in the Raman spectra of heavily boron-doped diamond to the vibrations of carbon atoms. The 500 cm-1Raman band shifts with either carbon or boron isotope substitution and may be associated with vibrations of paired or clustered boron. The absence of a superconducting transition (down to 1.6 K) in diamonds synthesized in the Co-C-B system at 1900 K correlates with the small boron concentration deduced from lattice parameters.
authors.affiliation: Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Russia.
authors.forename: Evgeny A
authors.initials: EA
authors.lastname: Ekimov
authors.affiliation: Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Russia.
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Sidorov
authors.affiliation: Physics Department, Moscow State University, 119992 Moscow, Russia.
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Zoteev
authors.affiliation: Institute for Nuclear Research, Russian Academy of Sciences, 142190 Troitsk, Russia.
authors.forename: Julia B
authors.initials: JB
authors.lastname: Lebed
authors.affiliation: Los Alamos National Laboratory, 87545 Los Alamos, NM, USA.
authors.forename: Joe D
authors.initials: JD
authors.lastname: Thompson
authors.affiliation: Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Russia.
authors.forename: Sergey M
authors.initials: SM
authors.lastname: Stishov
keywords: Raman spectroscopy; boron-doped diamond; isotope effect; superconductivity