title: Polarization shaping of high-order harmonics in laser-aligned molecules.
abstract: The present work reports on the generation of short-pulse coherent extreme ultraviolet radiation of controlled polarization. The proposed strategy is based on high-order harmonics generated in pre-aligned molecules. Field-free molecular alignment produced by a short linearly-polarized infrared laser pulse is used to break the isotropy of a gas medium. Driving the aligned molecules by a circularly-polarized infrared pulse allows to transfer the anisotropy of the medium to the polarization of the generated harmonic light. The ellipticity of the latter is controlled by adjusting the angular distribution of the molecules at the time they interact with the driving pulse. Extreme ultraviolet radiation produced with high degree of ellipticity (close to circular) is demonstrated.
authors.affiliation: Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, P.O. Box 1527, GR-711 10 Heraklion, Crete, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Skantzakis
authors.affiliation: Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, P.O. Box 1527, GR-711 10 Heraklion, Crete, Greece.|Department of Physics, University of Crete, P.O. Box 2208, GR71003 Heraklion, Crete, Greece.
authors.forename: S
authors.initials: S
authors.lastname: Chatziathanasiou
authors.affiliation: Dipartimento di Fisica Politecnico, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
authors.forename: P A
authors.initials: PA
authors.lastname: Carpeggiani
authors.affiliation: ELI-ALPS, ELI-Hu Kft., Dugonics tér 13, H-6720 Szeged Hungary.|Institute of Photonics and Nanotechnologies (IFN)-Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, 20133 Milano, Italy.|Dipartimento di Fisica Politecnico, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Sansone
authors.affiliation: ELI-ALPS, ELI-Hu Kft., Dugonics tér 13, H-6720 Szeged Hungary.
authors.forename: A
authors.initials: A
authors.lastname: Nayak
authors.affiliation: Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, P.O. Box 1527, GR-711 10 Heraklion, Crete, Greece.
authors.forename: D
authors.initials: D
authors.lastname: Gray
authors.affiliation: Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, P.O. Box 1527, GR-711 10 Heraklion, Crete, Greece.|ELI-ALPS, ELI-Hu Kft., Dugonics tér 13, H-6720 Szeged Hungary.
authors.forename: P
authors.initials: P
authors.lastname: Tzallas
authors.affiliation: Foundation for Research and Technology-Hellas, Institute of Electronic Structure and Laser, P.O. Box 1527, GR-711 10 Heraklion, Crete, Greece.|Department of Physics, University of Crete, P.O. Box 2208, GR71003 Heraklion, Crete, Greece.|ELI-ALPS, ELI-Hu Kft., Dugonics tér 13, H-6720 Szeged Hungary.
authors.forename: D
authors.initials: D
authors.lastname: Charalambidis
authors.affiliation: Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47870, F-21078 DIJON Cedex, France.
authors.forename: E
authors.initials: E
authors.lastname: Hertz
authors.affiliation: ELI-ALPS, ELI-Hu Kft., Dugonics tér 13, H-6720 Szeged Hungary.|Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47870, F-21078 DIJON Cedex, France.
authors.forename: O
authors.initials: O
authors.lastname: Faucher