Quantum devices based on oxide 2-dimensional electron gases

Missions

Oxide interfaces often display unexpected phases arising from charge, spin and orbital reconstruction in a non-centrosymmetric environment. Paradigmatic examples include the two-dimensional electron gases (2DEGs) forming in SrTiO3 (STO) and KTaO3 (KTO) when these materials are interfaced with insulating oxides such as LaAlO3 (LAO) or AlOx. These 2DEGs are superconducting (up to 2 K for (111)-oriented KTO), possess high electron mobilities and display Rashba spin-orbit coupling (SOC) that may be harnessed to perform spin-charge interconversion.

We propose an ambitious research program to explore the physics of oxide 2DEGs with a view towards their application in quantum  technologies. We have identified oxide 2DEGs as promising candidates for the definition of quantum dots to be used as spinqubits whose readout will take advantage of Rashba SOC. The candidate will grow the samples and participate in the design and characterization of the quantum dots in collaboration with external partners. In parallel, the project will focus on hetero- and mesostructures (quantum point contacts, tunnel junctions, Josephson junctions, SQUIDs, etc) whose investigation should shed light on the nature of the normal and superconducting states, on their connection with Rashba SOC and will clarify the potential of oxide 2DEGs as platforms for nonreciprocal electronics and topological quantum computing. The candidate will prepare the samples and lead the magnetotransport experiments.

Work context

The project will take place in the Oxitronics group of the Unité Mixte de Physique CNRS/Thales (U. Paris-Saclay, Palaiseau), a world-leading laboratory in condensed matter physics and the cradle of spintronics. The Oxitronics group has a long experience in oxide electronics and spintronics, from sample growth (with a unique UHV cluster combining multiple growth and characterization chambers), device patterning (UV, e-beam), characterization (XRD, scanning probe microscopy) and magnetotransport. The work will be done in strong partnership with the group of Nicolas Bergeal from the LPEM of ESPCI (Paris). Both teams have a long history of collaboration with multiple joint publications in high profile journals. The position will be financed by the IQARO EU project gathering labs from Salerno, Naples, Copenhagen, Göteborg, Paris and Krakow with the French companies Thales and RIBER.

SCIENTIFIC Skills

Required: Condensed matter physics, electron transport, quantum transport, quantum physics, superconductivity;
Recommended: physics of oxide materials, spintronics, spin-charge interconversion.

TECHNICAL Skills

Required: magnetotransport (dc, ac, rf), cryogenics, data analysis with e.g. Python;
Recommended: thin films growth by pulsed laser deposition and/or sputtering, scanning probe microscopy, X-ray spectroscopies.