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arXiv · 2302.07286

Helicity-dependent Ultrafast Photocurrents in Weyl Magnet Mn$_3$Sn

Dominik Hamara·Gunnar F. Lange·Farhan Nur Kholid·Anastasios Markou·Claudia Felser·Robert-Jan Slager·Chiara Ciccarelli
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Abstract

We present an optical pump-THz emission study on non-collinear antiferromagnet Mn$_3$Sn. We show that Mn$_3$Sn acts as a source of THz radiation when irradiated by femtosecond laser pulses. The polarity and amplitude of the emitted THz fields can be fully controlled by the polarisation of optical excitation. We explain the THz emission with the photocurrents generated via the photon drag effect by combining various experimental measurements as a function of pump polarisation, magnetic field, and sample orientation with thorough symmetry analysis of response tensors.

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Dominik Hamara, Gunnar F. Lange, Farhan Nur Kholid, Anastasios Markou, Claudia Felser, Robert-Jan Slager, Chiara Ciccarelli. 2023-02-14. Helicity-dependent Ultrafast Photocurrents in Weyl Magnet Mn$_3$Sn. https://doi.org/10.1038/s42005-023-01440-5

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