title: Full characterization and optimization of a femtosecond ultraviolet laser source for time and angle-resolved photoemission on solid surfaces.
abstract: A novel experimental apparatus for time and angle-resolved photoemission on solid surfaces is presented. A 6.28 eV laser source operating at 250 kHz repetition rate is obtained by frequency mixing in nonlinear beta barium borate crystals. This UV light source has a high photon flux of 10(13) photons/s with relatively low number of photons/pulse so that Fermi surface mapping over a wide region of the Brillouin zone is possible while mitigating space charge effects. The UV source has been fully characterized spatially, spectrally, and temporally. Its potential for time and angle-resolved photoemission is demonstrated through Fermi surface mapping and photoexcited electron dynamics in Bismuth. True femtosecond time resolution <65 fs is obtained while the energy resolution of 70 meV appears to be mainly limited by the laser bandwidth.
authors.affiliation: Laboratoire d'Optique Appliquée, ENSTA-CNRS-Ecole Polytechnique, UMR 7639, 91761 Palaiseau, France.
authors.forename: J
authors.initials: J
authors.lastname: Faure
authors.forename: J
authors.initials: J
authors.lastname: Mauchain
authors.forename: E
authors.initials: E
authors.lastname: Papalazarou
authors.forename: W
authors.initials: W
authors.lastname: Yan
authors.forename: J
authors.initials: J
authors.lastname: Pinon
authors.forename: M
authors.initials: M
authors.lastname: Marsi
authors.forename: L
authors.initials: L
authors.lastname: Perfetti