Nanoscale transient polarization gratings

Laura Foglia; Björn Wehinger; Giovanni Perosa; Riccardo Mincigrucci; Enrico Allaria; Francesco Armillotta; Alexander Brynes; Riccardo Cucini; Dario De Angelis; Giovanni De Ninno; W. Dieter Engel; Danny Fainozzi; Luca Giannessi; Nupur N. Khatu; Simone Laterza; Ettore Paltanin; Jacopo Stefano Pelli-Cresi; Giuseppe Penco; Denny Puntel; Primož Rebernik Ribič; Filippo Sottocorona; Mauro Trovò; Clemens von Korff Schmising; Kelvin Yao; Claudio Masciovecchio; Stefano Bonetti; Filippo Bencivenga

arXiv · 2310.15734

Nanoscale transient polarization gratings

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Abstract

We present the generation of transient polarization gratings at the nanoscale, achieved using a tailored accelerator configuration of the FERMI free electron laser. We demonstrate the capabilities of such a transient polarization grating by comparing its induced dynamics with the ones triggered by a more conventional intensity grating on a thin film ferrimagnetic alloy. While the signal of the intensity grating is dominated by the thermoelastic response of the system, such a contribution is suppressed in the case of the polarization grating. This exposes helicity-dependent magnetization dynamics that have so-far remained hidden under the large thermally driven response. We anticipate nanoscale transient polarization gratings to become useful for the study of any physical, chemical and biological systems possessing chiral symmetry.

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Laura Foglia, Björn Wehinger, Giovanni Perosa, Riccardo Mincigrucci, Enrico Allaria, Francesco Armillotta, Alexander Brynes, Riccardo Cucini, Dario De Angelis, Giovanni De Ninno, W. Dieter Engel, Danny Fainozzi, Luca Giannessi, Nupur N. Khatu, Simone Laterza, Ettore Paltanin, Jacopo Stefano Pelli-Cresi, Giuseppe Penco, Denny Puntel, Primož Rebernik Ribič, Filippo Sottocorona, Mauro Trovò, Clemens von Korff Schmising, Kelvin Yao, Claudio Masciovecchio, Stefano Bonetti, Filippo Bencivenga. 2023-10-24. Nanoscale transient polarization gratings. https://arxiv.org/abs/2310.15734

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