Edge States in Lateral p-n Junctions in Inverted Band HgTe Quantum Wells

Abstract

We investigate lateral p-n junctions, electrostatically defined in 14 nm-wide HgTe-based quantum wells (QWs) with inverted band structure. The p-n junctions resistances are close to $h/2e^2$, consistent with some previous experiments on 8-10 nm QWs, and the current-voltage characteristics are highly linear, indicating the transport via ballistic helical edge states. Shot noise measurements are performed in order to further verify the underlying transport mechanism. We discuss the role of unknown inelastic relaxation rates in the leads and in the edge channels for the correct interpretation of the noise data. Although the interpretation in favor of the helical edge states seems more consistent, a definite conclusion can not be drawn based on the present experiment. Our approach looks promising for the study of short quasi-ballistic edges in topological insulators (TIs) in suitable geometry.

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Cited by in corpus (7)

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• Topological protection brought to light by the time-reversal symmetry breaking
• Quantum Fluctuation of the Quantum Geometric Tensor and its Manifestation as Intrinsic Hall Signatures in Time-Reversal Invariant Systems
• Strategy for accurate thermal biasing at the nanoscale
• Universal bottleneck for thermal relaxation in disordered metallic films
• What can we learn from nonequilibrium response of a strange metal?
• Wiedemann-Franz behavior at the Weyl points in compressively strained HgTe