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arXiv · 2302.00803

Inversion Symmetry Breaking in Epitaxial Ultrathin Bi (111) Films

Hadass S. Inbar·Muhammad Zubair·Jason T. Dong·Aaron N Engel·Connor P. Dempsey·Yu Hao Chang·Shinichi Nishihaya·Shoaib Khalid·Alexei V. Fedorov·Anderson Janotti·Chris J. Palmstrøm
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Abstract

Bismuth (Bi) films hold potential for spintronic devices and topological one-dimensional edge transport. Large-area high-quality (111) Bi ultrathin films are grown on InSb (111)B substrates. Strong film-substrate interactions epitaxially stabilize the (111) orientation and lead to inversion symmetry breaking. We resolve the longstanding controversy over the Z_2 topological assignment of bismuth and show that the surface states are topologically trivial. Our results demonstrate that interfacial bonds prevent the semimetal-to-semiconductor transition predicted for freestanding bismuth layers, highlighting the importance of controlled functionalization and surface passivation in two-dimensional materials.

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Hadass S. Inbar, Muhammad Zubair, Jason T. Dong, Aaron N Engel, Connor P. Dempsey, Yu Hao Chang, Shinichi Nishihaya, Shoaib Khalid, Alexei V. Fedorov, Anderson Janotti, Chris J. Palmstrøm. 2023-02-02. Inversion Symmetry Breaking in Epitaxial Ultrathin Bi (111) Films. https://arxiv.org/abs/2302.00803

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