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arXiv · 2208.02060

Large nonsaturating magnetoresistance, weak anti-localization and non-trivial topological states in SrAl$_2$Si$_2$

Sudip Malick·A. B. Sarkar·Antu Laha·M. Anas·V. K. Malik·Amit Agarwal·Z. Hossain·J. Nayak
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Abstract

We explore the electronic and topological properties of single crystal SrAl$_2$Si$_2$ using magnetotransport experiments in conjunction with first-principle calculations. We find that the temperature-dependent resistivity shows a pronounced peak near 50 K. We observe several remarkable features at low temperatures, such as large non-saturating magnetoresistance, Shubnikov-de Haas oscillations and cusp-like magneto-conductivity. The maximum value of magnetoresistance turns out to be 459\% at 2 K and 12 T. The analysis of the cusp-like feature in magneto-conductivity indicates a clear signature of weak anti-localization. Our Hall resistivity measurements confirm the presence of two types of charge carriers in SrAl$_2$Si$_2$, with low carrier density.

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Sudip Malick, A. B. Sarkar, Antu Laha, M. Anas, V. K. Malik, Amit Agarwal, Z. Hossain, J. Nayak. 2022-08-03. Large nonsaturating magnetoresistance, weak anti-localization and non-trivial topological states in SrAl$_2$Si$_2$. https://doi.org/10.1103/physrevb.106.075105

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