A5023908345- Physics of Superconductivity and Magnetism
- Electronic and Structural Properties of Oxides
- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- Semiconductor materials and devices
- Quantum and electron transport phenomena
- Advanced Electrical Measurement Techniques
- Quantum Information and Cryptography
- Surface and Thin Film Phenomena
- Atomic and Subatomic Physics Research
- Iron-based superconductors research
- Advanced Materials Characterization Techniques
- Superconducting and THz Device Technology
- Semiconductor Quantum Structures and Devices
- Theoretical and Computational Physics
- Cold Atom Physics and Bose-Einstein Condensates
- Superconducting Materials and Applications
- Quantum Mechanics and Applications
- Terahertz technology and applications
- Mechanical and Optical Resonators
- Magnetic properties of thin films
- Rare-earth and actinide compounds
- Superconductivity in MgB2 and Alloys
- Ferroelectric and Negative Capacitance Devices
- Particle accelerators and beam dynamics
Centre National de la Recherche Scientifique
2014-2024
Laboratoire de Physique et d’Étude des Matériaux
2015-2024
Sorbonne Université
2015-2024
Université Paris Sciences et Lettres
2015-2024
ESPCI Paris
2015-2024
Université Sorbonne Nouvelle
2023
Sorbonne University Abu Dhabi
2023
Institute of Electrical and Electronics Engineers
2020
University of Catania
2020
Université Paris Cité
2019
In this Letter, we show that a superconducting two-dimensional electron gas is formed at the LaTiO3/SrTiO3 interface whose transition temperature can be modulated by back-gate voltage. The consists of two types carriers: majority low-mobility carriers always present, and few high-mobility ones injected electrostatic doping. calculation spatial distribution in confinement potential shows electrons responsible for superconductivity set edge extension tuned field effect.
Abstract The discovery of two-dimensional electron gases (2DEGs) at oxide interfaces—involving electrons in narrow d -bands—has broken new ground, enabling the access to correlated states that are unreachable conventional semiconductors based on s - and p electrons. There is a growing consensus emerging properties these novel quantum wells—such as 2D superconductivity magnetism—are intimately connected specific orbital symmetries 2DEG sub-band structure. Here we show crystal orientation...
The transmission of Cooper pairs between two weakly coupled superconductors produces a superfluid current and phase difference; the celebrated Josephson effect. Because time-reversal parity symmetries, there is no without difference superconductors. Reciprocally, when those symmetries are broken, an anomalous supercurrent can exist in absence bias or, equivalently, shift $\varphi_0$ current. We report on observation hybrid junctions fabricated with topological insulator Bi$_2$Se$_3$...
Abstract The recent development in the fabrication of artificial oxide heterostructures opens new avenues field quantum materials by enabling manipulation charge, spin and orbital degrees freedom. In this context, discovery two-dimensional electron gases (2-DEGs) at LaAlO 3 /SrTiO interfaces, which exhibit both superconductivity strong Rashba spin-orbit coupling (SOC), represents a major breakthrough. Here, we report on realisation field-effect device, whose physical properties, including...
Abstract In LaTiO 3 /SrTiO and LaAlO heterostructures, the bending of SrTiO conduction band at interface forms a quantum well that contains superconducting two-dimensional electron gas (2-DEG). Its carrier density electronic properties, such as superconductivity Rashba spin-orbit coupling can be controlled by electrostatic gating. this article we show Fermi energy lies intrinsically near top well. Beyond filling threshold, electrons added gating escape from well, hence limiting possibility...
Oxide heterostructures are of great interest both for fundamental and applicative reasons. In particular the two-dimensional electron gas at LaAlO$_3$/SrTiO$_3$ or LaTiO$_3$/SrTiO$_3$ interfaces displays many different physical properties functionalities. However there clear indications that interface electronic state is strongly inhomogeneous therefore it crucially relevant to investigate possible intrinsic mechanisms underlying this inhomogeneity. Here electrostatic potential confining...
Oxide interfaces exhibit a broad range of physical effects stemming from broken inversion symmetry. In particular, they can display non-reciprocal phenomena when time reversal symmetry is also broken, e.g., by the application magnetic field. Examples include direct and inverse Edelstein (DEE, IEE) that allow interconversion between spin currents charge currents. The DEE IEE have been investigated in based on perovskite SrTiO3 (STO), albeit separate studies focusing one or other....
After almost twenty years of intense work on the celebrated LaAlO3/SrTiO3system, recent discovery a superconducting two-dimensional electron gas (2-DEG) in (111)-oriented KTaO3-based heterostructures injects new momentum to field oxides interface. However, while both interfaces share common properties, experiments also suggest important differences between two systems. Here, we report gate tunable superconductivity 2-DEGs generated at surface KTaO3 crystal by simple sputtering thin Al layer....
Rashba interfaces have emerged as promising platforms for spin-charge interconversion through the direct and inverse Edelstein effects. Notably, oxide-based two-dimensional electron gases display a large gate-tunable conversion efficiency, determined by transport measurements. However, visualization of Rashba-split bands in oxide is lacking, which hampers an advanced understanding their rich spin-orbit physics. Here, we investigate KTaO3 evidence using angle resolved photoemission...
We demonstrate full frequency conversion in the microwave domain using a Josephson three-wave mixing device pumped at difference between frequencies of its fundamental eigenmodes. By measuring signal output as function intensity and phase three input signal, idler, pump tones, we show that functions controllable beam splitter or combiner for propagating modes single-photon level, accordance with theory. Losses point are found to be less than 10(-2). Potential applications include quantum...
The two-dimensional electron gas at the LaTiO${}_{3}$/SrTiO${}_{3}$ or LaAlO${}_{3}$/SrTiO${}_{3}$ oxide interfaces becomes superconducting when carrier density is tuned by gating. measured resistance and superfluid reveal an inhomogeneous superconductivity resulting from percolation of filamentary structures ``puddles'' with randomly distributed critical temperatures, embedded in a nonsuperconducting matrix. Following evidence that related to appearance high-mobility carriers, we model...
We present scanning tunneling microscopy and spectroscopy of the newly discovered superconductor CaC$_6$. The conductance spectra, measured between 3 K 15 K, show a clear superconducting gap in quasiparticle density states. function extracted from spectra is good agreement with conventional BCS theory $\Delta(0)$ = 1.6 $\pm$ 0.2 meV. possibility anisotropy two-gap superconductivity also discussed. In magnetic field, direct imaging vortices allows to deduce coherence length ab plane...
We have developed a masked ion irradiation technique to engineer the energy landscape for vortices in oxide superconductors. This approach associates possibility design geometry at nanoscale with unique capability adjust depth of wells vortices. enabled us unveil key role vortex channeling modulating amplitude field matching effects artificial landscape, and make latter govern flux dynamics over an unusually wide range temperatures applied fields high-temperature superconducting films.
We report on an experimental and theoretical study of the high-frequency mixing properties ion-irradiated YBa2Cu3O7 Josephson junctions embedded in THz antennas. investigated influence local oscillator power frequency device performances. The data are compared with predictions general three-port model for mixers which junction is described by resistively shunted model. A good agreement obtained conversion efficiency different ranges, spanning above below characteristic frequencies fc junctions.
In this Letter, we report the observation of correlation between two modes microwave radiation resulting from amplification quantum noise by Josephson parametric converter. This process, seen pump, can be viewed as down-conversion. The is measured an interference experiment displaying a contrast better than 99% with number photons per mode greater 250,000. Dispersive measurements mesoscopic systems and encryption benefit development.
The large diversity of exotic electronic phases displayed by two-dimensional superconductors confronts physicists with new challenges. These include the recently discovered quantum Griffith singularity in atomic Ga films, topological proximized insulators and unconventional Ising pairing transition metal dichalcogenide layers. In LaAlO3/SrTiO3 heterostructures, a gate tunable superconducting electron gas is confined well at interface between two insulating oxides. Remarkably, coexists both...