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DOE OSTI · 3388179

Toward Tunable Magnetic Dirac Semimetals: Mn Doping of Cd 3 As 2

Abstract

Magnetic impurities provide a route toward increasing functionality in electronic materials, often enabling new device concepts and architectures. In the case of topological semimetals, dilute magnetic doping presents a particularly attractive approach for inducing a Dirac to Weyl phase change via time reversal symmetry breaking. However, efforts to realize changes in the electronic structure have been limited by challenges in incorporating magnetic impurities into crystals with sufficiently high electron mobilities to detect them via transport or spectroscopic techniques. Here, we demonstrate incorporation of Mn into Cd 3 ⁢As 2 Dirac semimetal thin films grown by molecular beam epitaxy (MBE). Using As-rich growth conditions and [001] oriented thin films, Mn compositions of >10% are achieved. Films contain uniform distributions of Mn with no evidence of secondary phases and exhibit electron mobilities greater than 10 000–30 000 cm 2 /Vs up to 5% Mn. An evolution in the magnetization behavior along with the emergence of a second quantum oscillation frequency at low Mn concentrations provide preliminary evidence of Mn-induced changes in the electronic structure that are consistent with a Weyl phase. This work demonstrates the potential of magnetically doping topological semimetal thin films and a pathway for synthesizing them.

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BibTeXRIS

Rice, Anthony D. [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Leahy, Ian [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Ness, Herve [King's College, London (United Kingdom)], Norman, Andrew G. [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:000000016368521X), Heinselman, Karen N. [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Jiang, Chun‐Sheng [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Graf, David [Florida State University, Tallahassee, FL (United States). National High Magnetic Field Laboratory (MagLab)], Suslov, Alexey [Florida State University, Tallahassee, FL (United States). National High Magnetic Field Laboratory (MagLab)], Lany, Stephan [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000281278885), Van Schilfgaarde, Mark [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000312104459), Alberi, Kirstin [National Laboratory of the Rockies (NLR), Golden, CO (United States); University of Colorado, Boulder, CO (United States). Renewable and Sustainable Energy Institute (RSEI)] (ORCID:0000000252365568). 2026-07-07. Toward Tunable Magnetic Dirac Semimetals: Mn Doping of Cd 3 As 2. https://doi.org/10.1002/adfm.202600052

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