Ultrafast time-evolution of chiral Néel magnetic domain walls probed by circular dichroism in x-ray resonant magnetic scattering

DOI: 10.1038/s41467-022-28899-0

Authors: Cyril Leveille (Synchrotron SOLEIL) , Erick Burgos-Parra (Synchrotron SOLEIL; CNRS, Thales, Université Paris-Saclay) , Yanis Sassi (CNRS, Thales, Université Paris-Saclay) , Fernando Ajejas (CNRS, Thales, Université Paris-Saclay) , Valentin Chardonnet (Sorbonne Université, CNRS) , Emanuele Pedersoli (Elettra-Sincrotrone Trieste) , Flavio Capotondi (Elettra-Sincrotrone Trieste) , Giovanni De Ninno (Elettra-Sincrotrone Trieste; University of Nova Gorica) , Francesco Maccherozzi (Diamond Light Source) , Sarnjeet Dhesi (Diamond Light Source) , David M. Burn (Diamond Light Source) , Gerrit Van Der Laan (Diamond Light Source) , Oliver S. Latcham (University of Exeter) , Andrey V. Shytov (University of Exeter) , Volodymyr V. Kruglyak (University of Exeter) , Emmanuelle Jal (Sorbonne Université, CNRS) , Vincent Cros (CNRS, Thales, Université Paris-Saclay) , Jean-Yves Chauleau (SPEC, CEA, CNRS, Université Paris-Saclay) , Nicolas Reyren (CNRS, Thales, Université Paris-Saclay) , Michel Viret (SPEC, CEA, CNRS, Université Paris-Saclay) , Nicolas Jaouen (Synchrotron SOLEIL)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 13

State: Published (Approved)
Published: March 2022

Abstract: Non-collinear spin textures in ferromagnetic ultrathin films are attracting a renewed interest fueled by possible fine engineering of several magnetic interactions, notably the interfacial Dzyaloshinskii-Moriya interaction. This allows for the stabilization of complex chiral spin textures such as chiral magnetic domain walls (DWs), spin spirals, and magnetic skyrmions among others. We report here on the behavior of chiral DWs at ultrashort timescale after optical pumping in perpendicularly magnetized asymmetric multilayers. The magnetization dynamics is probed using time-resolved circular dichroism in x-ray resonant magnetic scattering (CD-XRMS). We observe a picosecond transient reduction of the CD-XRMS, which is attributed to the spin current-induced coherent and incoherent torques within the continuously varying spin texture of the DWs. We argue that a specific demagnetization of the inner structure of the DW induces a flow of spins from the interior of the neighboring magnetic domains. We identify this time-varying change of the DW texture shortly after the laser pulse as a distortion of the homochiral Néel shape toward a transient mixed Bloch-Néel-Bloch texture along a direction transverse to the DW.

Diamond Keywords: Spintronics; Ferromagnetism

Subject Areas: Materials, Physics

Facility: DiProI at FERMI

Added On: 28/03/2022 14:28

Documents:
s41467-022-28899-0.pdf

Discipline Tags:

Surfaces Quantum Materials Physics Electronics Magnetism Materials Science interfaces and thin films

Technical Tags: