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arXiv · 1409.5382

Novel Differential Conductance Oscillations in Asymmetric Quantum Point Contacts

Hao Zhang·Phillip M. Wu·Albert M. Chang
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Abstract

Small differential conductance oscillations as a function of source-drain bias were observed and systematically studied in an asymmetric quantum point contact (QPC). These oscillations become significantly suppressed in a small in-plane magnetic field ($\sim~0.7~T$) or at higher temperatures ($\sim~800~mK$). Qualitatively, their temperature evolution can be simulated numerically based on smearing of the Fermi distribution, whereas features near zero-bias cannot. Single particle scenarios are unsatisfactory in accounting for the oscillations, suggesting that they are likely caused by electron and spin correlation effects.

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Hao Zhang, Phillip M. Wu, Albert M. Chang. 2015-01-05. Novel Differential Conductance Oscillations in Asymmetric Quantum Point Contacts. https://doi.org/10.1103/physrevb.91.195150

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