Suppressing carrier density in (BixSb1-x)2Te3 films using Cr2O3 interfacial layers

Abstract

Band structure engineering and interfacial buffer layers have been demonstrated as effective means to tune the Fermi level in topological insulators (TI). In particular, the charge compensated compound (BixSb1-x)2Te3 (BST) plays a critical role in the molecular beam epitaxy growth of magnetic TIs. Here we introduce a strategy of exploiting epitaxial Cr2O3 as a buffer layer and amorphous Cr2O3 as a capping layer in the growth of BST films. These films exhibit carrier density lower than 1012/cm2 over a wide range of Bi contents and higher mobility than BST films directly grown on Al2O3 substrate, shedding light on the importance of interfacial layers for TI films and paving a new avenue to the application of magnetic BST films.

5 pages, 3 figures, Invited article to a Special issue in Journal of Physics D: Applied Physics

References in corpus (9)

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Cited by in corpus (5)

• Buffer-layer-controlled Nickeline vs Zinc-Blende/Wurtzite-type MnTe growths on c-plane Al2O3 substrates
• Atomic-Layer-Controlled Magnetic Orders in MnBi2Te4-Bi2Te3 Topological Heterostructures
• Resilient Growth of Highly Crystalline Topological Insulator-Superconductor Heterostructure Enabled by Ex-situ Nitride Film
• Effects of GaAs buffer layer on quantum anomalous Hall insulator Vy(BixSb1-x)2-yTe3
• Tuning Carrier Type and Density in Highly Conductive and Infrared-Transparent (Bi1-xSbx)2Te3 films