title: Laser-driven formation of transient local ferromagnetism in FeRh thin films.
abstract: The antiferromagnetic to ferromagnetic phase transition in FeRh can be induced globally by either heating the material above its phase transition temperature or applying a combination of external stimuli (such as mechanical strain, electric/magnetic fields) on the material preheated close to its transition temperature. On the other hand, to locally induce this phase transition is more desirable for applications and requires a confined source of energy such as a focused laser beam. Here we combine laser excitation with X-ray magnetic imaging to determine the effect of laser heating on the local and transient magnetization of FeRh using time-resolved photoelectron emission microscopy. Excitation by an ultrashort laser pulse generates a local ferromagnetic state within 0.6ns which recovers its initial antiferromagnetic state after a further 2ns. The form of the domains during the growth and diminution of ferromagnetic ordering suggests an intrinsic speed limit for magnetic and structural changes.
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, D-12489 Berlin, Germany. Electronic address: uenal@mbi-berlin.de.
authors.forename: A A
authors.initials: AA
authors.lastname: Ünal
authors.affiliation: Gebze Teknik Üniversitesi, Temel Bilimler Fakültesi, Fizik Bölümü, TR-41400 Gebze/Kocaeli, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Parabas
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, D-12489 Berlin, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Arora
authors.affiliation: Institut für Ionenstrahlphysik und Materialforschung, Helmholtz-Zentrum Dresden-Rossendorf, D-01328 Dresden, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Ehrler
authors.affiliation: School of Computer Science, University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Barton
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, D-12489 Berlin, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Valencia
authors.affiliation: Institut für Ionenstrahlphysik und Materialforschung, Helmholtz-Zentrum Dresden-Rossendorf, D-01328 Dresden, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Bali
authors.affiliation: School of Computer Science, University of Manchester, Manchester M13 9PL, United Kingdom.
authors.forename: T
authors.initials: T
authors.lastname: Thomson
authors.affiliation: Gebze Teknik Üniversitesi, Temel Bilimler Fakültesi, Fizik Bölümü, TR-41400 Gebze/Kocaeli, Turkey.
authors.forename: F
authors.initials: F
authors.lastname: Yildiz
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, D-12489 Berlin, Germany. Electronic address: florian.kronast@helmholtz-berlin.de.
authors.forename: F
authors.initials: F
authors.lastname: Kronast