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Title: Enhancement of 2D topological semimetal transport properties by current annealing
Observation of intrinsic quantum transport properties of two-dimensional (2D) topological semimetals can be challenging due to suppression of high mobility caused by extrinsic factors introduced during fabrication. We demonstrate current annealing as a method to substantially improve electronic transport properties of 2D topological semimetal flakes. Contact resistance and resistivity were improved by factors up to [Formula: see text] and [Formula: see text], respectively, in devices based on exfoliated flakes of two topological semimetals, ZrSiSe and BaMnSb 2 . Using this method, carrier mobility in ZrSiSe was improved by a factor of 3800, resulting in observation of record-high mobility for exfoliated ZrSiSe. Quantum oscillations in annealed ZrSiSe appeared at magnetic fields as low as 5 T, and magnetoresistance increased by a factor of 10 4 . We argue that a thermal process underlies this improvement. Finally, Raman spectroscopy and analysis of quantum oscillations in ZrSiSe indicate that the phonon modes and Fermi surface area are unchanged by current annealing.  more » « less
Award ID(s):
1848281
NSF-PAR ID:
10422641
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
11
ISSN:
0003-6951
Page Range / eLocation ID:
113101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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