Influence of magnetocrystalline anisotropy on the magnetization dynamics of magnetic microstructures

Abstract

Abstract. The study of magnetodynamics using stroboscopic time-resolved xray photoemission electron microscopy (TR-XPEEM) involves an intrinsic time scale provided by the pulse structure of the synchrotron radiation. In the usual multibunch operation mode, the time span between two subsequent light pulses is too short to allow a relaxation of the system into the ground state before the next pump-probe cycle starts. Using a deflection gating mechanism described in this paper we are able to pick the photoemission signal resulting from selected light pulses. Thus, PEEM measurements can be carried out in a flexible timing scheme with longer delays between two light pulses. Using this technique the magnetodynamics of both Permalloy and Iron structures has been investigated. The differences in the dynamic response on a short magnetic field pulse are discussed with respect to the magnetocrystalline anisotropy.

Time resolved X-ray Resonant Magnetic Scattering in reflection geometry

“…The resulting delay scan yields an element and time resolved sequence of the precessional dynamics in the sample. We emphasize that tr-XRMS measures the individual magnetic moments in contrast to tr-MOKE 16 , tr-PEEM 18,19 or tr-STXM 20,21 experiments, where typically the dynamics of domain structures like Landau patterns or vortex core reversal is monitored. Due to the photon-in photon-out technique, there is no charging effect to worry about as may be the case for PEEM experiments.…”

“…For magnetic alloys and for magnetic heterostructures it is desirable to have a method which not only has sufficient time resolution but also provides element selective information. For domain wall and vortex dynamics, time-resolved Photoemission Electron Microscopy (tr-PEEM) 18,19 and time resolved Scanning Transmission Xray Microscopy (tr-STXM) 20,21 experiments are powerful element selective tools using resonant absorption. These techniques, however, image domains rather than individual moments.…”

Magnetic nanostructures for advanced technologies: fabrication, metrology and challenges

“…However, since synchrotrons are pulsed sources, pump-probe and therefore time-resolved magnetic imaging may be accomplished in PEEM with temporal resolution below 100 ps. Magnetization dynamics have been recorded with time-resolved PEEM [172,[176][177][178]. With the eventual improvement of the spatial resolution, we expect that PEEM will have an even more prominent role in magnetic characterization because it would be possible to spatially and temporally resolve the magnetization of individual magnetic nanostructures with relative ease of sample preparation.…”

Adaption of a diffractometer for time-resolved X-ray resonant magnetic scattering

“…We emphasize that tr-XRMS measures the coherent dynamics of individual magnetic moments in variable magnetic fields in a fast and direct way. This can be done via PEEM experiments as well (Raabe et al, 2005); however, in most publications using element-selective techniques the authors concentrate on the dynamics of domain structures like Landau patterns (Kaiser et al, 2009;Vogel et al, 2003) or vortex core reversal (Bocklage et al, 2008;Van Waeyenberge et al, 2006). Owing to the photon-in-photon-out technique used in our set-up, there is no charging or magnetic field effect to worry about.…”

“…For magnetic alloys and for magnetic heterostructures it is desirable to have a method which not only has sufficient time resolution but also provides element-selective information. For domain wall and vortex dynamics, timeresolved photoemission electron microscopy (tr-PEEM) (Kaiser et al, 2009;Vogel et al, 2003;Raabe et al, 2005) and time-resolved scanning transmission X-ray microscopy (Bocklage et al, 2008;Van Waeyenberge et al, 2006) experiments are powerful element-selective tools using resonant absorption.…”