Growth and characterization of $\alpha$-Sn thin films on In- and Sb-rich reconstructions of InSb(001)

Aaron N. Engel; Connor P. Dempsey; Hadass S. Inbar; Jason T. Dong; Shinichi Nishihaya; Yu Hao Chang; Alexei V. Fedorov; Makoto Hashimoto; Donghui Lu; Christopher J. Palmstrøm

arXiv · 2311.16352

Growth and characterization of $\alpha$-Sn thin films on In- and Sb-rich reconstructions of InSb(001)

Aaron N. Engel·Connor P. Dempsey·Hadass S. Inbar·Jason T. Dong·Shinichi Nishihaya·Yu Hao Chang·Alexei V. Fedorov·Makoto Hashimoto·Donghui Lu·Christopher J. Palmstrøm

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Abstract

$\alpha$-Sn thin films can exhibit a variety of topologically non-trivial phases. Both studying the transitions between these phases and making use of these phases in eventual applications requires good control over the electronic and structural quality of $\alpha$-Sn thin films. $\alpha$-Sn growth on InSb often results in out-diffusion of indium, a p-type dopant. By growing $\alpha$-Sn via molecular beam epitaxy on the Sb-rich c(4$\times$4) surface reconstruction of InSb(001) rather than the In-rich c(8$\times$2), we demonstrate a route to substantially decrease and minimize this indium incorporation. The reduction in indium concentration allows for the study of the surface and bulk Dirac nodes in $\alpha$-Sn via angle-resolved photoelectron spectroscopy without the common approaches of bulk doping or surface dosing, simplifying topological phase identification. The lack of indium incorporation is verified in angle-resolved and -integrated ultraviolet photoelectron spectroscopy as well as in clear changes in the Hall response.

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Aaron N. Engel, Connor P. Dempsey, Hadass S. Inbar, Jason T. Dong, Shinichi Nishihaya, Yu Hao Chang, Alexei V. Fedorov, Makoto Hashimoto, Donghui Lu, Christopher J. Palmstrøm. 2023-11-27. Growth and characterization of $\alpha$-Sn thin films on In- and Sb-rich reconstructions of InSb(001). https://arxiv.org/abs/2311.16352

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