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Updated: Jun 22, 2025

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Gate-tunable subband degeneracy in semiconductor nanowires
Yuhao Wang1, Wenyu Song1, Zhan Cao2
1Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, 100084 Beijing, China.
Abstract:
Degeneracy and symmetry have a profound relation in quantum systems. Here, we report gate-tunable subband degeneracy in PbTe nanowires with a nearly symmetric cross-sectional shape. The degeneracy is revealed in electron transport by the absence of a quantized plateau. Utilizing a dual gate design, we can apply an electric field to lift the degeneracy, reflected as emergence of the plateau. This degeneracy and its tunable lifting were challenging to observe in previous nanowire experiments, possibly due to disorder. Numerical simulations can qualitatively capture our observation, shedding light on device parameters for future applications.
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