Femtosecond Single-Shot Imaging of Nanoscale Ferromagnetic Order in Co/Pd Multilayers Using Resonant X-Ray Holography

Th. Wang , Dl. Zhu , B. Wu , C. Graves , S. Schaffert , T. Rander , L. Muller , B. Vodungbo (1) , C. Baumier (2, 3) , D. P. Bernstein , B. Brauer , V. Cros (4) , S. de Jong , R. Delaunay (2) , A. Fognini , R. Kukreja , S. Lee , V. Lopez-Flores , J. Mohanty , B. Pfau , H. Popescu (3) , Maurizio Sacchi (3, 5) , A. B. Sardinha (1) , F. Sirotti (3) , Philippe Zeitoun (1) , M. Messerschmidt , J. J Turner , W. F. Schlotter , O. Hellwig , R. Mattana (4) , N. Jaouen (3) , F. Fortuna (6) , Y. Acremann , C. Gutt , H. A. Durr , E. Beaurepaire (7) , C. Boeglin (7) , S. Eisebitt , G. Grubel , J. Luning (2, 3) , J. Stohr , A. O. Scherz

1 LOA - Laboratoire d'optique appliquée
2 LCPMR - Laboratoire de Chimie Physique - Matière et Rayonnement
3 SSOLEIL - Synchrotron SOLEIL
4 Laboratoire Albert Fert (ex-UMPhy Unité mixte de physique CNRS/Thales)
5 INSP - Institut des Nanosciences de Paris
6 CSNSM INSTR
7 IPCMS - Institut de Physique et Chimie des Matériaux de Strasbourg

We present the first single-shot images of ferromagnetic, nanoscale spin order taken with femtosecond x-ray pulses. X-ray-induced electron and spin dynamics can be outrun with pulses shorter than 80 fs in the investigated fluence regime, and no permanent aftereffects in the samples are observed below a fluence of 25 mJ/cm(2). Employing resonant spatially muliplexed x-ray holography results in a low imaging threshold of5 mJ/cm(2). Our results open new ways to combine ultrafast laser spectroscopy with sequential snapshot imaging on a single sample, generating a movie of excited state dynamics.

Mots clés: FREE-ELECTRON LASER; DYNAMICS

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Matériaux

Th. Wang, Dl. Zhu, B. Wu, C. Graves, S. Schaffert, et al.. Femtosecond Single-Shot Imaging of Nanoscale Ferromagnetic Order in Co/Pd Multilayers Using Resonant X-Ray Holography. Physical Review Letters, 2012, 108, pp.267403. ⟨10.1103/PhysRevLett.108.267403⟩. ⟨in2p3-00724499⟩