Topological Insulator Bi2Se3 Nanowire Field Effect Transistors

Abstract

Topological insulator is characterized as a new class of materials which have an insulating band gap in the bulk and gapless surface state which is protected by its intrinsic time-reversal symmetry. Here, we report high-performance topological insulator nanowire field effect transistors (FETs) with sharp turn-on, clear cutoff current, large On/Off current ratio (~ 108) and well-saturated, strong inversion-mode output current-voltage characteristics. The metallic electron transport at surface, with effective mobility of 200 cm2V-1s-1 ~ 1000 cm2V-1s-1, and bulk conduction, with activation energy close to band gap of bulk Bi2Se3 can be effectively separated and tuned by gated field effect. We also report the first experimental observation of anomalous Aharonov-Bohm oscillation in Bi2Se3 nanowire FET under strong surface disorder. The magnetotransport properties demonstrated here of topological insulator nanostructure provide effective approaches of surface states modulations, and can enable more spintronics device applications and sensing applications.