Quantized conductance in a one-dimensional ballistic oxide nanodevice

A. Jouan; G. Singh; E. Lesne; D. C. Vaz; M. Bibes; A. Barthélémy; C. Ulysse; D. Stornaiuolo; M. Salluzzo; S. Hurand; J. Lesueur; C. Feuillet-Palma; N. Bergeal

arXiv · 1903.12134

Quantized conductance in a one-dimensional ballistic oxide nanodevice

A. Jouan·G. Singh·E. Lesne·D. C. Vaz·M. Bibes·A. Barthélémy·C. Ulysse·D. Stornaiuolo·M. Salluzzo·S. Hurand·J. Lesueur·C. Feuillet-Palma·N. Bergeal

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Abstract

Electric-field effect control of two-dimensional electron gases (2-DEG) has enabled the exploration of nanoscale electron quantum transport in semiconductors. Beyond these classical materials, transition metal-oxide-based structures have d-electronic states favoring the emergence of novel quantum orders absent in conventional semiconductors. In this context, the LaAlO3/SrTiO3 interface that combines gate-tunable superconductivity and sizeable spin-orbit coupling is emerging as a promising platform to realize topological superconductivity. However, the fabrication of nanodevices in which the electronic properties of this oxide interface can be controlled at the nanoscale by field-effect remains a scientific and technological challenge. Here, we demonstrate the quantization of conductance in a ballistic quantum point contact (QPC), formed by electrostatic confinement of the LaAlO3/SrTiO3 2-DEG with a split-gate. Through finite source-drain voltage, we perform a comprehensive spectroscopic investigation of the 3d energy levels inside the QPC, which can be regarded as a spectrometer able to probe Majorana states in an oxide 2-DEG.

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A. Jouan, G. Singh, E. Lesne, D. C. Vaz, M. Bibes, A. Barthélémy, C. Ulysse, D. Stornaiuolo, M. Salluzzo, S. Hurand, J. Lesueur, C. Feuillet-Palma, N. Bergeal. 2019-03-28. Quantized conductance in a one-dimensional ballistic oxide nanodevice. https://arxiv.org/abs/1903.12134

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