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DOE OSTI · 1993272

Thin-film TaAs: Developing a platform for Weyl semimetal devices

Nelson, Jocienne N.·Rice, Anthony D.·Kurleto, Rafal·Shackelford, Amanda·Sierzega, Zachary·Hao, Peipei·Berggren, Bryan S.·Jiang, Chun-Sheng·Norman, Andrew G.·Holtz, Megan E.·Mangum, John S.·Leahy, Ian A.·Heinselman, Karen N.·Ness, Herve·van Schilfgaarde, Mark·Dessau, Daniel S.·Alberi, Kirstin
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Abstract

MX monopnictide compounds (M = Nb,Ta, X = As,P) are prototypical 3D Weyl semimetals (WSMs) that have been shown in bulk single crystal form to have potential for a wide variety of novel devices due to topologically protected band structures and high mobilities. However, very little is known about thin-film synthesis, which is essential to enable device applications. We synthesize TaAs(001) epilayers by molecular beam epitaxy on GaAs(001) and provide an experimental phase diagram illustrating conditions for single-phase, single-crystal-like growth. We investigate the relationship between nanoscale defects and electronic structure using angle-resolved photoemission spectroscopy, kelvin probe force microscopy, and transmission electron microscopy. Our results provide a roadmap and platform for developing 3D WSMs for device applications.

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36 MATERIALS SCIENCEangle-resolved photoemission spectroscopydefectsdisorderinterfacesmagnetotransportmolecular beam epitaxyscanning probe microscopysynthesisthin filmtopological semimetal

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Nelson, Jocienne N., Rice, Anthony D., Kurleto, Rafal, Shackelford, Amanda, Sierzega, Zachary, Hao, Peipei, Berggren, Bryan S., Jiang, Chun-Sheng, Norman, Andrew G., Holtz, Megan E., Mangum, John S., Leahy, Ian A., Heinselman, Karen N., Ness, Herve, van Schilfgaarde, Mark, Dessau, Daniel S., Alberi, Kirstin. 2023-07-10. Thin-film TaAs: Developing a platform for Weyl semimetal devices. https://doi.org/10.1016/j.matt.2023.06.018

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