title: Far-infrared conductivity measurements of pair breaking in superconducting Nb 0.5 Ti 0.5 N thin films induced by an external magnetic field.
abstract: We report the complex optical conductivity of a superconducting thin film of Nb 0.5 Ti 0.5 N in an external magnetic field. The field was applied parallel to the film surface and the conductivity extracted from far-infrared transmission and reflection measurements. The real part shows the superconducting gap, which we observe to be suppressed by the applied magnetic field. We compare our results with the pair-breaking theory of Abrikosov and Gor'kov and confirm directly the theory's validity for the optical conductivity.
authors.affiliation: Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Xiaoxiang
authors.initials: X
authors.lastname: Xi
authors.forename: J
authors.initials: J
authors.lastname: Hwang
authors.forename: C
authors.initials: C
authors.lastname: Martin
authors.forename: D B
authors.initials: DB
authors.lastname: Tanner
authors.forename: G L
authors.initials: GL
authors.lastname: Carr