title: Superconducting gap in MgB(2): electronic Raman scattering measurements of single crystals.
abstract: Polarization-resolved Raman scattering measurements were performed on MgB(2) single crystals to determine the magnitude, symmetry, and temperature dependence of the superconducting gap. A single sharp peak due to Cooper pair breaking appears in the electronic continuum below T(c), reaching a maximum Raman shift of 105 +/- 1 cm(-1) [2 Delta(0)/k(B)T(c) = 3.96 +/- 0.09] and showing up to 5 cm(-1) anisotropy between polarized and depolarized spectra. The temperature dependence of 2 Delta follows that predicted from BCS theory, while the anisotropy decreases with decreasing temperature. It is concluded that the Raman results are consistent with a slightly anisotropic s-wave gap in a conventional BCS superconductor.
authors.affiliation: Superconductivity Research Laboratory, International Superconductivity Technology Center, 1-10-13 Shinonome, Koto-ku, Tokyo, 135-0062, Japan.
authors.forename: J W
authors.initials: JW
authors.lastname: Quilty
authors.forename: S
authors.initials: S
authors.lastname: Lee
authors.forename: A
authors.initials: A
authors.lastname: Yamamoto
authors.forename: S
authors.initials: S
authors.lastname: Tajima