arXiv:1904.00254 [cond-mat.mtrl-sci]AbstractReferencesReviewsResources
Basal-plane growth of cadmium arsenide by molecular beam epitaxy
David A. Kealhofer, Honggyu Kim, Timo Schumann, Manik Goyal, Luca Galletti, Susanne Stemmer
Published 2019-03-30Version 1
(001)-oriented thin films of the three-dimensional Dirac semimetal cadmium arsenide can realize a quantum spin Hall insulator and other kinds of topological physics, all within the flexible architecture of epitaxial heterostructures. Here, we report a method for growing (001) cadmium arsenide films using molecular beam epitaxy. The introduction of a thin indium arsenide wetting layer improves surface morphology and structural characteristics, as measured by x-ray diffraction and reflectivity, atomic force microscopy, and scanning transmission electron microscopy. The electron mobility of 50-nm-thick films is found to be 9300 cm2/Vs at 2 K, comparable to the highest-quality films grown in the conventional (112) orientation. This work demonstrates a simple experimental framework for exploring topological phases that are predicted to exist in proximity to the three-dimensional Dirac semimetal phase.