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arXiv · 2401.12432

Electronic Noise Spectroscopy of Quasi-2D van der Waals Antiferromagnetic Semiconductors

Abstract

We investigated low-frequency current fluctuations, i.e. electronic noise, in FePS3 van der Waals, layered antiferromagnetic semiconductor. The noise measurements have been used as noise spectroscopy for advanced materials characterization of the charge carrier dynamics affected by spin ordering and trapping states. Owing to the high resistivity of the material, we conducted measurements on vertical device configuration. The measured noise spectra reveal pronounced Lorentzian peaks of two different origins. One peak is observed only near the Neel temperature and it is attributed to the corresponding magnetic phase transition. The second Lorentzian peak, visible in the entire measured temperature range, has the characteristics of the trap-assisted generation-recombination processes similar to those in conventional semiconductors but shows a clear effect of the spin order reconfiguration near the Neel temperature. The obtained results contribute to understanding the electron and spin dynamics in this type of antiferromagnetic semiconductors and demonstrate the potential of electronic noise spectroscopy for advanced materials characterization.

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Subhajit Ghosh, Zahra Ebrahim Nataj, Fariborz Kargar, Alexander A. Balandin. 2024-01-23. Electronic Noise Spectroscopy of Quasi-2D van der Waals Antiferromagnetic Semiconductors. https://arxiv.org/abs/2401.12432

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