title: Low-energy electrodynamics of superconducting diamond.
abstract: Heavily boron-doped, diamond films can become superconducting with critical temperatures Tc well above 4 K. Here we first measure the reflectivity of such a film down to 5 cm(-1), by also using coherent synchrotron radiation. We thus determine the optical gap 2Delta, the field penetration depth lambda, the range of action of the Ferrell-Glover-Tinkham sum rule, and the electron-phonon spectral function alpha2F(omega). We conclude that diamond behaves as a dirty BCS superconductor.
authors.affiliation: CNR-INFM Coherentia and Dipartimento di Fisica, Università di Roma La Sapienza, Piazzale A. Moro, 2, 00185 Roma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Ortolani
authors.forename: S
authors.initials: S
authors.lastname: Lupi
authors.forename: L
authors.initials: L
authors.lastname: Baldassarre
authors.forename: U
authors.initials: U
authors.lastname: Schade
authors.forename: P
authors.initials: P
authors.lastname: Calvani
authors.forename: Y
authors.initials: Y
authors.lastname: Takano
authors.forename: M
authors.initials: M
authors.lastname: Nagao
authors.forename: T
authors.initials: T
authors.lastname: Takenouchi
authors.forename: H
authors.initials: H
authors.lastname: Kawarada