title: Far-IR excitations in Cd2Re2O7 in the normal and superconducting states.
abstract: Cd(2)Re(2)O(7) is a pyrochlore superconductor with a transition temperature T(c) near 1 K. We report on the far-infrared optical properties of Cd(2)Re(2)O(7) at temperatures above and below T(c) with a particular emphasis on changes in the spectrum below T(c). Seventeen phonon modes are observed in the normal state optical conductivity spectrum of Cd(2)Re(2)O(7) at low temperatures in good agreement with a factor group analysis. In the superconducting state, a softening (~1 cm(-1)) of the phonon modes at 35 and 61 cm(-1) occurs and thermal reflectance spectra show the development of two additional strong absorption features, near 9.6 and 19.3 cm(-1). The dominant presence of lattice vibrational modes in the optical spectrum suggests that electron-phonon interaction plays an important role in the normal and superconducting state properties of Cd(2)Re(2)O(7).
authors.affiliation: Department of Physics, Brock University, St Catharines, ON, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Hajialamdari
authors.forename: F S
authors.initials: FS
authors.lastname: Razavi
authors.forename: D A
authors.initials: DA
authors.lastname: Crandles
authors.forename: R K
authors.initials: RK
authors.lastname: Kremer
authors.forename: M
authors.initials: M
authors.lastname: Reedyk