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arXiv · 2311.08953

Hall-effect in the MnBi_2Te_4 crystal using silicon nitride nanomembrane via contacts

Abstract

Utilizing an interplay between band topology and intrinsic magnetism, the two-dimensional van der Waals (vdW) system MnBi_2Te_4 provides an ideal platform for realizing exotic quantum phenomena and offers great opportunities in the emerging field of antiferromagnetic spintronic technology. Yet, the fabrication of MnBi_2Te_4-based nanodevices is hindered by the high sensitivity of this material, which quickly degrades when exposed to air or to elevated temperatures. Here, we demonstrate an alternative route of fabricating vdW-MnBi_2Te_4-based electronic devices using the cryogenic dry transfer of a printable circuit embedded in an inorganic silicon nitride membrane. The electrical connections between the thin crystal and the top surface of the membrane are established through via contacts. Our magnetotransport study reveals that this innovative via contact approach enables exploring the MnBi_2Te_4-like sensitive 2D materials and engineering synthetic heterostructures as well as complex circuits based on the two-dimensional vdW systems.

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Mickey Martini, Tommaso Confalone, Yejin Lee, Bastian Rubrecht, Giuseppe Serpico, Sanaz Shokri, Christian N. Saggau, Domenico Montemurro, Valerii M. Vinokur, Anna Isaeva, Kornelius Nielsch, Nicola Poccia. 2023-11-27. Hall-effect in the MnBi_2Te_4 crystal using silicon nitride nanomembrane via contacts. https://doi.org/10.1063/5.0170335

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