title: Measurements of the inverse Faraday effect from relativistic laser interactions with an underdense plasma.
abstract: Magnetic fields in excess of 7 MG have been measured with high spatial and temporal precision during interactions of a circularly polarized laser pulse with an underdense helium plasma at intensities up to 1x10(19) W cm(-2). The fields, while of the form expected from the inverse Faraday effect for a cold plasma, are much larger than expected, and have a duration approaching that of the high intensity laser pulse ( <3 psec). These observations can be explained by particle-in-cell simulations in 3D. The simulations show that the magnetic field is generated by fast electrons which spiral around the axis of the channel created by the laser field.
authors.affiliation: Imperial College of Science, Technology & Medicine, Prince Consort Road, London SW7 2BZ, United Kingdom.
authors.forename: Z
authors.initials: Z
authors.lastname: Najmudin
authors.forename: M
authors.initials: M
authors.lastname: Tatarakis
authors.forename: A
authors.initials: A
authors.lastname: Pukhov
authors.forename: E L
authors.initials: EL
authors.lastname: Clark
authors.forename: R J
authors.initials: RJ
authors.lastname: Clarke
authors.forename: A E
authors.initials: AE
authors.lastname: Dangor
authors.forename: J
authors.initials: J
authors.lastname: Faure
authors.forename: V
authors.initials: V
authors.lastname: Malka
authors.forename: D
authors.initials: D
authors.lastname: Neely
authors.forename: M I
authors.initials: MI
authors.lastname: Santala
authors.forename: K
authors.initials: K
authors.lastname: Krushelnick