Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 15: Magnetization / Demagnetization Dynamics I

MA 15.3: Vortrag

Dienstag, 27. März 2012, 10:15–10:30, H 1012

Theoretical study of the time evolution of magnetization induced via the ultrafast inverse Faraday effect — •Daria Popova, Andreas Bringer, and Stefan Blügel — Peter Grünberg Institut & Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany

Ultrafast optical control of the magnetic state of a medium is a subject that attracts much scientific interest. Manipulation of the magnetic order by light on sub-picosecond time scales can be realized by the inverse Faraday effect (IFE) [1]. In these experiments circularly polarized high-intensity laser pulses with the length of several tens of femtoseconds are used to excite the magnetic system of the sample. The important principles of this effect are still unclear.

We describe the IFE via the stimulated Raman-like scattering process, which was suggested to be responsible for the magnetization reversal by light [2]. We show [3] that a system is brought to a new magnetic state after the action of a femtosecond circularly polarized laser pulse due to this process. We solve the time-dependent Schrödinger equation to model the IFE in atoms coupled with the exchange interaction in a crystal field environment. We study the time evolution of the magnetization during the action of light and magnetic oscillations, which are excited in the system.

We are thankful for the support by the FANTOMAS project.

[1] A. Kimel et al., Nature 435, 655 (2005).

[2] F. Hansteen et al., Phys. Rev. B 73, 014421 (2006).

[3] D. Popova, A. Bringer, S. Blügel, accepted to Phys. Rev. B.