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arXiv · 2309.02331

Ultrafast optical polarimetry in magnetic phases of Kondo semi metal CeSb

M. Naseska·N. Zhigadlo·Z. Jagličić·E. Goreshnik·T. Mertelj
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Abstract

We investigated photoinduced ultrafast transient dynamics in different magnetic phases in CeSb by means of the time resolved magneto-optical spectroscopy. We observe a distinctive coherent oscillations in the ground-state antiferromagnetic (AF) phase and the high-magnetic field ferromagnetic (F) phase. While the AF-phase oscillations frequencies match the recent Raman scattering findings the F-phase oscillation frequency does not correspond to the previously observed magnetic excitation. The large spectroscopic factor, g=3.94, and optical polarization properties suggest that it corresponds to a previously undetected Ce^{3+} coherent crystal-field state excitation. The AF-phase oscillations show no magnetic field dependence so their lattice origin cannot be entirely excluded. The non-oscillatory part of the transients is qualitatively similar in all investigated magnetic phases with a faster sub-picosecond dynamics in the ferromagnetic and ferro-para-magnetic phases and is attributed to differences in the electronic structure, which affect the photo-excited quasiparticle energy relaxation kinetics.

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M. Naseska, N. Zhigadlo, Z. Jagličić, E. Goreshnik, T. Mertelj. 2023-09-05. Ultrafast optical polarimetry in magnetic phases of Kondo semi metal CeSb. https://arxiv.org/abs/2309.02331

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