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arXiv · 1910.13228

Multi-frequency Shubnikov-de Haas oscillations in topological semimetal Pt$_2$HgSe$_3$

Diego Mauro·Hugo Henck·Marco Gibertini·Michele Filippone·Enrico Giannini·Ignacio Gutierrez-Lezama·Alberto F. Morpurgo
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Abstract

Monolayer jacutingaite (Pt$_2$HgSe$_3$) has been recently identified as a candidate quantum spin Hall system with a 0.5 eV band gap, but no transport measurements have been performed so far on this material, neither in monolayer nor in the bulk. By using a dedicated high-pressure technique, we grow crystals enabling the exfoliation of 50-100 nm thick layers and the realization of devices for controlled transport experiments. Magnetoresistance measurements indicate that jacutingaite is a semimetal, exhibiting Shubnikov-de Haas (SdH) resistance oscillations with a multi-frequency spectrum. We adapt the Lifshitz-Kosevich formula to analyze quantitatively the SdH resistance oscillations in the presence of multiple frequencies, and find that the experimental observations are overall reproduced well by band structure ab-initio calculations for bulk jacutingaite. Together with the relatively high electron mobility extracted from the experiments ($\approx 2000$ cm$^2$/Vs, comparable to what is observed in WTe$_2$ crystals of the same thickness), our results indicate that monolayer jacutingaite should provide an excellent platform to investigate transport in 2D quantum spin Hall systems.

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Diego Mauro, Hugo Henck, Marco Gibertini, Michele Filippone, Enrico Giannini, Ignacio Gutierrez-Lezama, Alberto F. Morpurgo. 2019-10-29. Multi-frequency Shubnikov-de Haas oscillations in topological semimetal Pt$_2$HgSe$_3$. https://doi.org/10.1088/2053-1583%2Fab7689

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