A5027966973- Quantum and electron transport phenomena
- Strong Light-Matter Interactions
- Graphene research and applications
- Semiconductor Quantum Structures and Devices
- Thermal Radiation and Cooling Technologies
- Mechanical and Optical Resonators
- 2D Materials and Applications
- Atomic and Subatomic Physics Research
- Advanced NMR Techniques and Applications
- Semiconductor Lasers and Optical Devices
- Quantum, superfluid, helium dynamics
- Diamond and Carbon-based Materials Research
- NMR spectroscopy and applications
- Molecular Junctions and Nanostructures
- Quantum Information and Cryptography
- Plasmonic and Surface Plasmon Research
- Carbon Nanotubes in Composites
- Quantum Electrodynamics and Casimir Effect
- Photonic Crystals and Applications
- Advanced Thermodynamics and Statistical Mechanics
- Photonic and Optical Devices
- Neural Networks and Reservoir Computing
- Thermal properties of materials
- Nonlinear Dynamics and Pattern Formation
- Terahertz technology and applications
École Normale Supérieure - PSL
2016-2025
École Normale Supérieure
2007-2025
Sorbonne Paris Cité
2016-2025
Sorbonne Université
2016-2025
Université Paris Cité
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Université Paris Sciences et Lettres
2016-2025
Institut Universitaire de France
2023-2025
Laboratoire de Physique de l'ENS
2007-2024
Thales (France)
2019
In view of the extensive use hexagonal boron nitride (hBN) in 2D material electronics, it becomes important to refine its dielectric characterization terms low-field permittivity and high-field strength conductivity up breakdown voltage. The present study aims at filling this gap using DC RF transport two Au-hBN-Au capacitor series variable thickness 10--100 nm range, made large high-pressure, high-temperature (HPHT) crystals a polymer derivative ceramics (PDC) crystals. We deduce an...
Strong electric field annihilation by particle-antiparticle pair creation, also known as the Schwinger effect, is a non-perturbative prediction of quantum electrodynamics. Its experimental demonstration remains elusive, threshold fields are extremely strong and beyond current reach. Here, we propose mesoscopic variant effect in graphene, which hosts Dirac fermions with an approximate electron-hole symmetry. Using transport measurements, report on universal 1d-Schwinger conductance at...
PtSe_{2} is a van der Waals material transitioning from an indirect band gap semiconductor to semimetal with increasing thickness. Its absorption threshold has been conjectured originate interband transitions. By quantitative comparison between broadband (0.8-3.0 eV) optical of high-quality exfoliated crystals and DFT ab initio simulations, we prove instead that the arises only direct This understanding allows us shed light on semiconductor-to-semimetal transition in emblematic strongly...
We revisit Mandel's notion that the degree of coherence equals indistinguishability by performing Hong-Ou-Mandel- (HOM-)type interferometry with single photons elastically scattered a cw resonantly driven excitonic transition an InAs/GaAs epitaxial quantum dot. present comprehensive study temporal profile photon coalescence phenomenon which shows can be tuned excitation laser source, in same way as their time. A new figure merit, time window, is introduced to quantify delay below two are...
Abstract Platinum diselenide () is a promising two‐dimensional (2D) material for the terahertz (THz) range as, unlike other transition metal dichalcogenides (TMDs), its bandgap can be uniquely tuned from semiconductor in near‐infrared to semimetal with number of atomic layers. This gives unique THz photonic properties that layer‐engineered. Here, we demonstrate controlled nonlinearity—tuned monolayer bulk —can realized wafer size polycrystalline through generation ultrafast photocurrents and...
Abstract Raman spectroscopy is widely used to assess the quality of 2D materials thin films. This report focuses on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi mathvariant="normal">P</mml:mi> mathvariant="normal">t</mml:mi> mathvariant="normal">S</mml:mi> <mml:msub> mathvariant="normal">e</mml:mi> <mml:mn>2</mml:mn> </mml:msub> </mml:mrow> </mml:math> , a noble transition metal dichalcogenide which has remarkable property transit from...
Nonequilibrium patterns in open systems are ubiquitous nature, with examples as diverse desert sand dunes, animal coat such zebra stripes, or geographic parasitic insect populations. A theoretical foundation that explains the basic features of a large class was given by Turing context chemical reactions and biological process morphogenesis. Analogs have also been studied optical where diffusion matter is replaced diffraction light. The unique polaritons semiconductor microcavities allow us...
Electrostatic gating is pervasive in materials science, yet its effects on the electronic band structure of has never been revealed directly by angle-resolved photoemission spectroscopy (ARPES), technique choice to non-invasively probe a material. By means state-of-the-art ARPES setup with sub-micron spatial resolution, we have investigated heterostructure composed Bernal-stacked bilayer graphene (BLG) hexagonal boron nitride and deposited graphite flake. voltage biasing latter, electric...
Terahertz emission between exciton-polariton branches in semiconductor microcavities is expected to be strongly stimulated the polariton laser regime due high density of particles lower state (final-state stimulation effect). However, nonradiative scattering processes depopulate upper and greatly hinder efficiency such terahertz sources. In this work, we suggest a scheme using multiple exploiting transition two interband located below exciton level. We compare loss rates single double cavity...
Abstract Characterizing quantum states of the electromagnetic field at microwave frequencies requires fast and sensitive detectors that can simultaneously probe field’s time-dependent amplitude its fluctuations. So far, this has been achieved by using either homodyne detection or digitizers. Both methods rely on extraction radiation through an amplification chain towards detector placed room temperature, thereby limiting time resolution to ~10-GHz bandwidth measurement chain. Additionally,...
Two-dimensional PtSe2 exhibits outstanding intrinsic properties such as high carrier mobility, tunable bandgap, broadband absorption and air stability, making it ideal for (opto)electronic applications. However, achieving crystalline quality films with controlled on low cost insulating substrates remains challenging. Here, highly semimetallic are grown by molecular beam epitaxy sapphire substrates. It is shown that a post-growth annealing remarkably improves the out-of-plane crystallinity of...
We report on the resonant optical pumping of $|\ifmmode\pm\else\textpm\fi{}1⟩$ spin states a single Mn dopant in an $\mathrm{InAs}/\mathrm{GaAs}$ quantum dot which is embedded charge tunable device. The experiment relies $W$ scheme transitions reached when suitable longitudinal magnetic field applied. achieved via excitation central $\ensuremath{\Lambda}$ system at neutral exciton ${X}^{0}$ energy. For specific gate voltage, redshifted photoluminescence charged ${X}^{\ensuremath{-}}$...
The current understanding of physical principles governing electronic transport in graphene field effect transistors (GFETs) has reached a level where we can model quite accurately device operation and predict intrinsic frequency limits performance. In this work, use knowledge to analyze DC RF properties bottom-gated on boron nitride exhibiting pronounced velocity saturation by substrate hyperbolic phonon polariton scattering, including Dirac pinch-off effect. We demonstrate maximum...
Abstract Engineering of the cooling mechanism is primary importance for development nanoelectronics. While radiation rather inefficient in current electronic devices, strong anisotropy 2D materials allows enhanced efficiency because their hyperbolic electromagnetic dispersion near phonon resonances them to sustain much larger (≈10 5 ) number radiating channels. In this review, addressed. The waves presented, and how spontaneous fluctuations a channel can radiate thermal energy its...
High-mobility hexagonal boron nitride (hBN)/graphene/hBN heterostructures are able to reach intrinsic limits of transport. Here, we investigate optoelectronic mixing, which is a demanding function combining efficient photodetection and fast carrier dynamics. Using such heterostructure embedded in coplanar waveguide, obtain record conversion efficiency about −40 dB for frequencies up 65 GHz. This performance obtained at high doping the photobolometric regime. We provide microscopic model...
Van der Waals (vdW) heterostructures host many-body quantum phenomena that can be tuned in situ using electrostatic gates. These gates are often microstructured graphite flakes naturally form plasmonic cavities, confining light discrete standing waves of current density due to their finite size. Their resonances typically lie the GHz - THz range, corresponding same $\mu$eV meV energy scale characteristic many effects materials they electrically control. This raises possibility built-in...
The optical spin Hall effect is a transport phenomenon of exciton polaritons in semiconductor microcavities, caused by the polaritonic spin-orbit interaction, which leads to formation textures. control via light injection double microcavity demonstrated. Angular rotations polarization pattern up 22° are observed and compared simple theoretical model. device geometry responsible for existence two polariton branches allows robust independent hence state emitted field, solution technologically...
We demonstrate time reversal of nuclear spin dynamics in highly magnetized dilute liquid (3)He-(4)He mixtures through effective inversion long-range dipolar interactions. These experiments, which involve using magic sandwich NMR pulse sequences to generate echoes, probe the spatiotemporal development turbulent and promise serve as a versatile tool for study control dynamic magnetization instabilities. also show that repeated sequence can be used dynamically stabilize modes precession are...
$1/f$ electronic noise is a conductance fluctuation, expressed in terms of mobility ``$\ensuremath{\alpha}$-noise'' by Hooge and Kleinpenning. Understanding this graphene key for high-performance electronics. Early investigations pointed out deviation from the standard formula, with free-carrier density substituted constant ${n}_{\mathrm{\ensuremath{\Delta}}}\ensuremath{\sim}{10}^{12}\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}2}$. Here we investigate hBN-encapsulated...
In low field nuclear magnetic resonance (NMR) it is desirable to combine proper characteristics of the detection scheme with a good signal noise ratio. For example, reduced coupling between sample and coil needed for NMR highly magnetized samples large bandwidth required in imaging (MRI). We discuss solution based on simple active feedback circuit that preserves ratio as opposed traditional solutions which do not. give illustrations its use experiments temperature hyperpolarized liquid 3He-...