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Quantum ballistic transport in constrictions of n-PbTe

G. Grabecki·J. Wrobel·T. Dietl·K. Byczuk·E. Papis·E. Kaminska·A. Piotrowska·G. Springholz·M. Pinczolits·G. Bauer
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Abstract

Conductance of submicron constrictions of PbTe:Bi was studied up to 8T and between 4.2K and 50mK. The structures were fabricated by electron beam lithography and chemical etching of high--electron mobility films grown by MBE on BaF_2. In the moderately strong magnetic fields perpendicular to the current, B>1T, the conductance shows accurate quantization in the units of 1e^2/h as a function of the side-gate voltage. In the absence of the field, a temperature-independent step structure, with an average step height approx. 1e^2/h, is observed. It is suggested that such a quantization may reflect the lifting of the Kramers degeneracy by the exchange interaction among the electrons, effective despite a large dielectric constant of bulk PbTe.

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G. Grabecki, J. Wrobel, T. Dietl, K. Byczuk, E. Papis, E. Kaminska, A. Piotrowska, G. Springholz, M. Pinczolits, G. Bauer. 1999-06-12. Quantum ballistic transport in constrictions of n-PbTe. https://doi.org/10.1103/physrevb.60.r5133

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