A5024290422- 2D Materials and Applications
- Graphene research and applications
- Mechanical and Optical Resonators
- Carbon Nanotubes in Composites
- Perovskite Materials and Applications
- MXene and MAX Phase Materials
- Chalcogenide Semiconductor Thin Films
- Force Microscopy Techniques and Applications
- Advanced MEMS and NEMS Technologies
- Advanced Thermoelectric Materials and Devices
- Gas Sensing Nanomaterials and Sensors
- Nanotechnology research and applications
- Quantum Dots Synthesis And Properties
- Quantum and electron transport phenomena
- Ga2O3 and related materials
- Molecular Junctions and Nanostructures
- Topological Materials and Phenomena
- Acoustic Wave Resonator Technologies
- ZnO doping and properties
- Analog and Mixed-Signal Circuit Design
- Copper-based nanomaterials and applications
- Advanced Memory and Neural Computing
- Advanced Semiconductor Detectors and Materials
- Semiconductor materials and interfaces
- Electrospun Nanofibers in Biomedical Applications
Centre de Nanosciences et de Nanotechnologies
2016-2025
Université Paris-Saclay
2016-2025
Centre National de la Recherche Scientifique
2013-2024
Université Paris-Sud
2016-2023
Synchrotron soleil
2021
Institut Català de Nanociència i Nanotecnologia
2011-2014
Université Paris Cité
2008-2013
Délégation Paris 7
2013
Sorbonne Paris Cité
2013
École Normale Supérieure - PSL
2007-2011
Nanocrystals are promising building blocks for the development of low-cost infrared optoelectronics. Gating a nanocrystal film in phototransistor geometry is commonly proposed as strategy to tune signal-to-noise ratio by carefully controlling carrier density within semiconductor. However, performance improvement has so far been quite marginal. With metallic electrodes, gate dependence photocurrent follows gate-induced change dark current. Graphene presents key advantages: (i) transparency...
Nanowires are widely used for energy harvesting, sensors, and solar cells. We report a study on the role of buffer layer in growth zinc oxide (ZnO) nanowires (NWs) synthesised by chemical bath deposition (CBD) method. To control thickness layer, multilayer coatings corresponding to one (100 nm thick), three layers (300 six (600 thick) ZnO sol-gel thin-films were used. The evolution morphology structure NWs was characterized scanning electron microscopy, X-ray diffraction, photoluminescence,...
A hallmark of mechanical resonators made from a single nanotube is that the resonance frequency can be widely tuned. Here, we take advantage this property to realize parametric amplification and self-oscillation. The gain as high 18.2 dB tends saturate at pumping due nonlinear damping. These measurements allow us determine coefficient linear damping force. corresponding rate lower than one obtained line shape (without pumping), supporting recently reported scenario describes in by...
Quantum interference in cross-conjugated molecules embedded solid-state devices was investigated by direct current-voltage and differential conductance transport measurements of anthraquinone (AQ)-based large area planar junctions. A thin film AQ grafted covalently on the junction base electrode diazonium electroreduction, while counter directly evaporated top molecular layer. Our technique provides evidence a quantum effect multiple CMOS compatible The is manifested pronounced dip close to...
Semiconducting 2D materials, such as transition metal dichalcogenides (TMDs), are emerging in nanomechanics, optoelectronics, and thermal transport. In each of these fields, perfect control over material properties including strain, doping, heating is necessary, especially on the nanoscale. Here, we study clean devices consisting membranes single-layer MoS2 suspended pillar arrays. Using Raman photoluminescence spectroscopy, have been able to extract, separate simulate different...
Combining single-layer two-dimensional semiconducting transition-metal dichalcogenides (TMDs) with a graphene layer in van der Waals heterostructures offers an intriguing means of controlling the electronic properties through these heterostructures. Here, we report and structural transferred $\mathrm{W}{\mathrm{S}}_{2}$ on epitaxial using micro-Raman spectroscopy, angle-resolved photoemission spectroscopy measurements, density functional theory (DFT) calculations. The results show good as...
The crystallographic stacking order in multilayer graphene plays an important role determining its electronic properties. It has been predicted that a rhombohedral (ABC) displays conducting surface state with flat dispersion. In such band, the of electron-electron correlation is enhanced, possibly resulting high ${T}_{\mathrm{c}}$ superconductivity, charge-density wave, or magnetic orders. Clean experimental band-structure measurements ABC-stacked specimens are missing because samples...
Two-dimensional monochalcogenides (MX) have been identified as a unique and promising class of layered materials in recent years. The valence band single-layer MX, predicted by theory, is inverted into bow-shaped (often referred to an sombrero) relatively flat dispersion, which expected give rise strongly correlated effects. inversion leads indirect gap, consistent with photoluminescence (PL) experiments, but PL provides no direct evidence the band. Here we demonstrate for hexagonal MX...
Abstract In atomically thin transition metal dichalcogenide semiconductors, there is a crossover from indirect to direct band gap as the thickness drops one monolayer, which comes with fast increase of photoluminescence signal. Here, we show that for different alloy compositions WS 2(1− x ) Se 2 this trend may be significantly affected by content and demonstrate sample highest ratio presents strongly reduced effect. The micro-PL intensity found bilayer ( = 0.8) decrease its maximum value...
Abstract The combination of monolayers different two-dimensional (2D) materials into van der Waals hetero-bilayer structures creates unprecedented physical phenomena, acting as a powerful tool for future devices. Understanding and exploiting these phenomena hinge on knowing the electronic structure hybridization structures. Here, we show strong effects arising between constitutive single layers SnS 2 /WSe grown by chemical vapor deposition. Surprisingly, valence band maximum position WSe is...
A low-cost sol–gel spin-coating technique is used in this study for the simple synthesis of eco-friendly ZnO multilayer films deposited on (100)-oriented silicon substrates ranging from 150 to 600 nm by adjusting spin coating rate.
Small changes in the structure of thin bidimensional transition metal dichalcogenides (TMDs) can radically alter overall material properties. Here, we investigate epitaxial self-organized boundary between two tungsten diselenide domains obtained by chemical vapor deposition: AB ferroelectric bilayer (noncentrosymmetric, <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mn>3</a:mn><a:mi>R</a:mi></a:mrow></a:math>-like) and conventional AA' (centrosymmetric, <b:math...
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 microwave operation of top-gated single carbon nanotube transistors. From transmission measurements in the 0.1−1.6 GHz range, we deduce device transconductance gm and gate−nanotube capacitance Cg micro- nanometric devices. A large frequency-independent ∼ 20 μS is observed short devices, which meets best dc results. The per unit gate length 60 aF/μm typical top gates a conventional oxide with ε 10. This value factor 3−5 below quantum which, according to recent simulations, favors...
Van der Waals (vdW) heterostructures obtained by stacking 2D materials offer a promising route for next generation devices combining different unique properties in completely new artificial materials. In particular, the vdW combine high mobility and optical that can be exploited optoelectronic devices. Since p-n junction is one of most fundamental units optoelectronics, we propose an approach its fabrication based on intrinsic n doped MoS2 p bilayer graphene hybrid interfaces. We demonstrate...
HgTe nanocrystals (NCs) enable broadly tunable infrared absorption, now commonly used to design light sensors. This material tends grow under multipodic shapes and does not present well-defined size distributions. Such point generates traps reduces the particle packing, leading a reduced mobility. It is thus highly desirable comprehensively explore effect of shape on their performance. Here, we show, using combination electron tomography tight binding simulations, that charge dissociation...
Abstract Nanomechanical resonators are built into phones, as filters or accelerometers, but they lack a knob to effectively tune the frequency at nanoscale when it’s easy on an octave tone of classical musical instrument like guitar string. Moreover, control deformation in nanomaterials, two-dimensional (2D) materials, tailor their electronic properties, i.e., straintronic, opens up avenues for applications force detection, bolometry quantum emitters. An accurate within these materials is...
Abstract GeSn alloys are promising materials for CMOS-compatible mid-infrared lasers manufacturing. Indeed, Sn alloying and tensile strain can transform them into direct bandgap semiconductors. This growing laser technology however suffers from a number of limitations, such as poor optical confinement, lack strain, thermal, defects management, all which poorly discussed in the literature. Herein, specific GeSn-on-insulator (GeSnOI) stack using stressor layers dielectric claddings is...
In two dimensional materials, substitutional doping during growth can be used to alter the electronic properties. Here, we report on stable of p-type hexagonal boron nitride (h-BN) using Mg-atoms as impurities in h-BN honeycomb lattice. We use micro-Raman spectroscopy, angle-resolved photoemission measurements (nano-ARPES) and Kelvin probe force microscopy (KPFM) study properties Mg-doped grown by solidification from a ternary Mg-B-N system. Besides observation new Raman line at ∼1347 cm-1...
The growth of bilayers two-dimensional (2D) materials on conventional 3D semiconductors results in 2D/3D hybrid heterostructures, which can provide additional advantages over more established while retaining some specificities 2D materials. Understanding and exploiting these phenomena hinge knowing the electronic properties hybridization structures. Here, we demonstrate that a rhombohedral-stacked bilayer (AB stacking) be obtained by molecular beam epitaxy tungsten diselenide (WSe2) gallium...
Twisted layers of atomically thin two-dimensional materials support a broad range quantum with engineered optical and transport properties. Transition metal dichalcogenides (TMDs) in the rhombohedral ($3R$, i.e., ${0}^{\ensuremath{\circ}}$ twist) crystal phase have been focus significant research interest applications due to their particular broken inversion symmetry. Here, we report experimental theoretical study $\mathrm{W}{\mathrm{Se}}_{2}$ homobilayers obtained stable $3R$ configuration...