Field-effect control of superconductivity and Rashba spin-orbit coupling in top-gated LaAlO3/SrTiO3 devices
S Hurand1, A Jouan1, C Feuillet-Palma1
1Laboratoire de Physique et d'Etude des Matériaux -CNRS-ESPCI ParisTech-UPMC, PSL Research University, 10 Rue Vauquelin, 75005 Paris, France.
Scientific Reports
|August 6, 2015
Summary
We developed a tunable LaAlO3/SrTiO3 device demonstrating control over superconductivity and spin-orbit coupling (SOC). This breakthrough enables new quantum materials and mesoscopic devices with tunable properties.
Area of Science:
- Quantum Materials Science
- Condensed Matter Physics
- Materials Science
Background:
- Artificial oxide heterostructures enable manipulation of quantum degrees of freedom.
- LaAlO3/SrTiO3 interfaces host two-dimensional electron gases (2-DEGs) with superconductivity and strong Rashba spin-orbit coupling (SOC).
Purpose of the Study:
- To realize a field-effect device based on LaAlO3/SrTiO3 interfaces.
- To demonstrate tunability of superconductivity and SOC via gating.
- To investigate the quantum phase transition and Rashba coupling behavior.
Main Methods:
- Fabrication of a field-effect LaAlO3/SrTiO3 device.
- Electrical transport measurements under varying gate voltages.
- Magneto-transport analysis to determine Rashba coupling strength.
Main Results:
- Tunable superconductivity and SOC achieved through top-gate voltage.
- Phase diagram reveals a field-effect-induced superconductor-to-insulator quantum phase transition.
- Rashba coupling constant found to increase linearly with interfacial electric field.
Conclusions:
- Field-effect gating provides a powerful tool to tune quantum properties of LaAlO3/SrTiO3 interfaces.
- This work paves the way for locally controlled mesoscopic devices utilizing superconductivity and SOC.
- Demonstrates a pathway for engineering novel quantum phenomena in oxide heterostructures.
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