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arXiv · 2211.11837

Topological field-effect transistor with quantized ON/OFF conductance of helical/chiral dislocation states

Xiaoyin Li·Feng Liu
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Abstract

Topology is a key ingredient driving the emergence of quantum devices. Topological field-effect transistor (TFET) has been proposed to outperform the conventional FET by replacing the ON state with topology-protected quantized conductance, while the OFF state remains the same normal insulating characteristics and hence bears similar drawbacks. Here, we demonstrate a proof-of-concept TFET having both ON and OFF quantized conductance, by switching between helical and chiral topological screw dislocation (SD) states in three-dimensional topological insulators. A pair of SDs are configured with one acting as channel and the other as gate controlled by local magnetic field. A reversible field-switching is achieved with the ON and OFF conductance of $2e^2/h$ and $e^2/h$, respectively, as shown by tight-binding quantum transport calculations. Furthermore, BaBiO$_3$ is shown as a candidate material having the desired topological SD states, based on first-principles calculations. Our findings open a new route to high-fidelity topological quantum devices.

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Xiaoyin Li, Feng Liu. 2022-11-21. Topological field-effect transistor with quantized ON/OFF conductance of helical/chiral dislocation states. https://doi.org/10.1103/physrevb.107.224101

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