The electronic relaxation times are determined via pump-probe optical spectroscopy using sub-15 fs pulses over a wide range of probe energies for two different cuprate superconductors. Based on the exact analytic solution for the electron relaxation, we extract values for the second moments of the Eliashberg functions. These values suggest a fundamental importance of the electron-phonon interaction and in particular polaronic effects in the superconducting pairing mechanism in the cuprates.
COBISS.SI-ID: 23499303
Femtosecond time-resolved optical spectroscopy was used to study photoexcited carrier relaxation dynamics in the intermediate-valence heavy-fermion system Yb1-xLuxAl3 (0?x?1). Given the demonstrated sensitivity of this experimental technique to the presence of the low-energy gaps in the charge excitation spectrum, the aim of this work was to study the effect of dilution of the Kondo lattice on its low-energy electronic structure. The results imply that in Yb1-xLuxAl3 the hybridization gap, resulting from hybridization of local moments and conduction electrons, persists up to 30% doping.
COBISS.SI-ID: 22907175