Uncovering the gap, Δ(ω): Measurement of the Re(σS/σN) in superconducting Tl2Ba2CaCu2O8

• Published in: Physica. C, Superconductivity Vol. 341-348; pp. 2223 - 2224
• Main Authors: Holcomb, M.J., Little, W.A.
• Format: Journal Article
• Language: English
• Published: 2000
• ISSN: 0921-4534
• DOI: 10.1016/S0921-4534(00)01025-X

AUTHors report measurements of both the normal-state reflectance and the superconducting- to normal-state reflectance ratio of a thin film sample of Tl2Ba2CaCu2O8 at near-normal incidence for photon energies between 0.09 and 4.5 eV. From these data,AUTHors have obtained the real part of the superconducting- to normal-state optical conductivity ratio, Re(sigma S/sigma N). This quantity can be related directly to structure in DELTA(omega) without the need to invoke Eliashberg theory.AUTHors find structure in DELTA(omega) for superconducting Tl2Ba2CaCu2O8 at low-energy, presumably due to electron-phonon coupling, and additional structure at approx 1.2 and 1.7 eV, which AUTHors attribute to an electronic component of the pairing interaction in this material. 7 refs.