title: Compression of X-ray Free Electron Laser Pulses to Attosecond Duration.
abstract: State of the art X-ray Free Electron Laser facilities currently provide the brightest X-ray pulses available, typically with mJ energy and several hundred femtosecond duration. Here we present one- and two-dimensional Particle-in-Cell simulations, utilising the process of stimulated Raman amplification, showing that these pulses are compressed to a temporally coherent, sub-femtosecond pulse at 8% efficiency. Pulses of this type may pave the way for routine time resolution of electrons in nm size potentials. Furthermore, evidence is presented that significant Landau damping and wave-breaking may be beneficial in distorting the rear of the interaction and further reducing the final pulse duration.
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.
authors.forename: James D
authors.initials: JD
authors.lastname: Sadler
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.
authors.forename: Ricky
authors.initials: R
authors.lastname: Nathvani
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.
authors.forename: Piotr
authors.initials: P
authors.lastname: Oleśkiewicz
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.
authors.forename: Luke A
authors.initials: LA
authors.lastname: Ceurvorst
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.
authors.forename: Naren
authors.initials: N
authors.lastname: Ratan
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.
authors.forename: Muhammad F
authors.initials: MF
authors.lastname: Kasim
authors.affiliation: Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon, OX11 0QX.
authors.forename: Raoul M G M
authors.initials: RM
authors.lastname: Trines
authors.affiliation: Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon, OX11 0QX.|Department of Physics, University of Strathclyde, John Anderson Building, 107 Rottenrow, Glasgow, G4 0NG.
authors.forename: Robert
authors.initials: R
authors.lastname: Bingham
authors.affiliation: Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU.|Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxon, OX11 0QX.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Norreys