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arXiv · 2004.06752

Probing photo-induced rearrangements in the NdNiO$_{3}$ magnetic spiral with polarization-sensitive ultrafast resonant soft x-ray scattering

K. R. Beyerlein·A. S. Disa·M Först·M. Henstridge·T. Gebert·T. Forrest·A. Fitzpatrick·C. Dominguez·J. Fowlie·M. Gibert·J. -M. Triscone·S. S. Dhesi·A. Cavalleri
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Abstract

We use resonant soft X-ray diffraction to track the photo-induced dynamics of the antiferromagnetic structure in a NdNiO$_{3}$ thin film. Femtosecond laser pulses with a photon energy of 0.61 eV, resonant with electron transfer between long-bond and short-bond nickel sites, are used to excite the material and drive an ultrafast insulator-metal transition. Polarization sensitive soft X-ray diffraction, resonant to the nickel L$_{3}$-edge, then probes the evolution of the underlying magnetic spiral as a function of time delay with 80 picosecond time resolution. By modelling the azimuthal dependence of the scattered intensity for different linear X-ray polarizations, we benchmark the changes of the local magnetic moments and the spin alignment. The measured changes are consistent with a reduction of the long-bond site magnetic moments and an alignment of the spins towards a more collinear structure at early time delays.

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K. R. Beyerlein, A. S. Disa, M Först, M. Henstridge, T. Gebert, T. Forrest, A. Fitzpatrick, C. Dominguez, J. Fowlie, M. Gibert, J. -M. Triscone, S. S. Dhesi, A. Cavalleri. 2020-04-14. Probing photo-induced rearrangements in the NdNiO$_{3}$ magnetic spiral with polarization-sensitive ultrafast resonant soft x-ray scattering. https://doi.org/10.1103/physrevb.102.014311

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