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arXiv · 1203.2843

Evidence for Charging Effects in CdTe/CdMgTe Quantum Point Contacts

M. Czapkiewicz·V. Kolkovsky·P. Nowicki·M. Wiater·T. Wojciechowski·T. Wojtowicz·J. Wróbel
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Abstract

Here we report on fabrication and low temperature magnetotransport measurements of quantum point contacts patterned from a novel two-dimensional electron system - CdTe/CdMgTe modulation doped heterostructure. From the temperature and bias dependence we ascribe the reported data to evidence for a weakly bound state which is naturally formed inside a CdTe quantum constrictions due to charging effects. We argue that the spontaneous introduction of an open dot is responsible for the replacement of flat conductance plateaus by quasi-periodic resonances with amplitude less than 2e^{2}/h, as found in our system. Additionally, below 1 K a pattern of weaker conductance peaks, superimposed upon wider resonances, is also observed.

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M. Czapkiewicz, V. Kolkovsky, P. Nowicki, M. Wiater, T. Wojciechowski, T. Wojtowicz, J. Wróbel. 2012-04-23. Evidence for Charging Effects in CdTe/CdMgTe Quantum Point Contacts. https://doi.org/10.1103/physrevb.86.165415

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