New data on Bi₂Sr₂CaCu₂O_8+δ (Bi2212) reveal interesting aspects of photoexcited superconductors. The electrons dynamics show that inelastic scattering by nodal quasiparticles decreases when the temperature is lowered below the critical value of the superconducting phase transition. This drop of electronic dissipation is astonishingly robust and survives to photoexcitation densities much larger than the value sustained by long-range superconductivity. The unconventional behavior of quasiparticle scattering is ascribed to superconducting correlations extending on a length scale comparable to the inelastic mean-free path. Our measurements indicate that strongly driven superconductors enter in a regime without phase coherence but finite pairing amplitude.

Date Published: 13 May 2016
PDF: 4 pages
Proc. SPIE 9835, Ultrafast Bandgap Photonics, 98351I (13 May 2016); doi: 10.1117/12.2222498

Published in SPIE Proceedings Vol. 9835:
Ultrafast Bandgap Photonics
Michael K. Rafailov; Eric Mazur, Editor(s)