Observation and control of the anomalous Aharonov-Bohm oscillation in enhanced-mode topological insulator nanowire field-effect transistors

摘要

Aharonov-Bohm (AB) oscillation is a quantum mechanical phenomenon which reveals the coupling of electromagnetic potentials with the electron wave function, affecting the phase of the wave function. Such a quantum interference effect can be demonstrated through the magnetotransport measurement focusing on low-dimensional electronic states. Here, we report the experimental observation of anomalous AB oscillation in an enhanced-mode topological insulator Bi2Se3 nanowire field-effect transistor (FET) under strong surface disorder, which is different from the reported AB oscillation in topological insulator nanostructures. The surrounding gate of the nanowire FET gives rise to tunability of the chemical potential and introduces strong disorder on the surface states, leading to primary oscillation with an anomalous h/e period. Furthermore, the oscillation exhibits a significant dependence on the gate voltage which has been preliminary explained with the quantization of the surface conduction channel. The experimental demonstration can be very attractive for further exploration of quantum phase interference through electrical approaches, enabling applications in future information and electromagnetic sensing technology.