A5074493928- Graphene research and applications
- 2D Materials and Applications
- Surface and Thin Film Phenomena
- Physics of Superconductivity and Magnetism
- Electron and X-Ray Spectroscopy Techniques
- Chalcogenide Semiconductor Thin Films
- Topological Materials and Phenomena
- Electronic and Structural Properties of Oxides
- Advanced Condensed Matter Physics
- Advanced Chemical Physics Studies
- Semiconductor materials and devices
- Quantum Dots Synthesis And Properties
- Quantum and electron transport phenomena
- MXene and MAX Phase Materials
- Magnetic properties of thin films
- Magnetic and transport properties of perovskites and related materials
- Nanowire Synthesis and Applications
- Perovskite Materials and Applications
- Semiconductor materials and interfaces
- Diamond and Carbon-based Materials Research
- High-pressure geophysics and materials
- Molecular Junctions and Nanostructures
- X-ray Spectroscopy and Fluorescence Analysis
- Advancements in Battery Materials
- ZnO doping and properties
Synchrotron soleil
2016-2025
Université Paris-Saclay
2016-2024
Elettra-Sincrotrone Trieste S.C.p.A.
2000-2018
University of Oxford
2018
Collaborative Innovation Center of Quantum Matter
2018
Tsinghua University
2018
University of Bath
2017
ALBA Synchrotron (Spain)
2014-2015
La Jolla Alcohol Research
2007-2013
Universidad Autónoma Metropolitana
2011
Because of its unique physical properties, graphene, a 2D honeycomb arrangement carbon atoms, has attracted tremendous attention. Silicene, the graphene equivalent for silicon, could follow this trend, opening new perspectives applications, especially due to compatibility with Si-based electronics. Silicene been theoretically predicted as buckled Si atoms and having an electronic dispersion resembling that relativistic Dirac fermions. Here we provide compelling evidence, from both structural...
Two-dimensional layered MoS2 shows great potential for nanoelectronic and optoelectronic devices due to its high photosensitivity, which is the result of indirect direct band gap transition when bulk dimension reduced a single monolayer. Here, we present an exhaustive study alignment relativistic properties van der Waals heterostructure formed between layers graphene. A sharp, high-quality MoS2-graphene interface was obtained characterized by micro-Raman spectroscopy, high-resolution X-ray...
The interlayer coupling can be used to engineer the electronic structure of van der Waals heterostructures (superlattices) obtain properties that are not possible in a single material. So far research has been focused on commensurate superlattices with long-ranged Moir\'e period. Incommensurate rotational symmetry but translational (in analogy quasicrystals) only rare nature, also interaction often assumed negligible due lack phase coherence. Here we report successful growth quasicrystalline...
2D layered materials have emerged in recent years as a new platform to host novel electronic, optical, or excitonic physics and develop unprecedented nanoelectronic energy applications. By definition, these are strongly anisotropic between the basal plane cross plane. The structural property anisotropies inside their plane, however, much less investigated. Black phosphorus, for example, is material that has such in-plane anisotropy. Here, rare chemical form of arsenic, called black-arsenic...
Ferromagnetic ordering of monolayer vanadium dichalcogenides (VSe2 and VS2) has been predicted by density functional theory (DFT), suggestive experimental evidence for magnetic in VSe2 monolayers reported. However, such ferromagnetic would be stark contradiction to the known paramagnetic nature bulk VSe2. Herein, we investigate electronic structure angle-resolved photoemission spectroscopy (ARPES) first-principles DFT. The ARPES measurements demonstrate absence spin-polarized bands close...
Moiré superlattices in twisted two-dimensional materials have generated tremendous excitement as a platform for achieving quantum properties on demand. However, the moiré pattern is highly sensitive to interlayer atomic registry, and current assembly techniques suffer from imprecise control of average twist angle, spatial inhomogeneity local distortions caused by random strain. We manipulated patterns hetero- homobilayers through in-plane bending monolayer ribbons, using tip an force...
Multilayer silicene, the silicon analogue of multilayer graphene, grown on silver (111) surfaces, possesses a honeycomb (√3 × √3)R30° reconstruction, observed by scanning tunnelling microscopy at room temperature, past initial formation dominant, 3×3 reconstructed, silicene monolayer. For few layers film we measure synchrotron radiation photoelectron spectroscopy, cone-like dispersion Brillouin zone centre due to band folding. π* and π states meet ∼0.25 eV below Fermi level, providing clear...
Artificial heterostructures assembled from van der Waals materials promise to combine without the traditional restrictions in heterostructure-growth such as lattice matching conditions and atom interdiffusion. Simple stacking of with diverse properties would thus enable fabrication novel or device structures atomically precise interfaces. Because covalent bonding these layered is limited molecular planes interaction between are very weak, only small changes electronic structure expected by...
The performance of MISTRAL is reported, the soft X-ray transmission microscopy beamline at ALBA light source (Barcelona, Spain) which primarily dedicated to cryo tomography (cryo-SXT) for three-dimensional visualization whole unstained cells spatial resolutions down 30 nm (half pitch). Short acquisition times allowing high-throughput and correlative studies have promoted cryo-SXT as an emerging cellular imaging tool structural cell biologists bridging gap between optical electron microscopy....
Abstract The polaron is a quasi-particle formed by conduction electron (or hole) together with its self-induced polarization in polar semiconductor or an ionic crystal. Among various polarizable examples of complex oxides, strontium titanate (SrTiO 3 ) one the most studied. Here we examine carrier type and interplay inner degrees freedom (for example, charge, lattice, orbital) SrTiO . We report experimental observation Fröhlich polarons, large at bare surface prepared vacuum annealing....
We report the scalable growth of aligned graphene and hexagonal boron nitride on commercial copper foils, where each film originates from multiple nucleations yet exhibits a single orientation. Thorough characterization our reveals uniform crystallographic electronic structures length scales ranging nanometers to tens centimeters. As we demonstrate with artificial twisted bilayers, these inexpensive versatile films are ideal building blocks for large-scale layered heterostructures...
Nanometric biocompatible Metal-Organic Frameworks (nanoMOFs) are promising candidates for drug delivery. Up to now, most studies have targeted the intravenous route, related pain and severe complications; whereas nanoMOFs oral administration, a commonly used non-invasive simpler remains however unexplored. We propose here biofriendly preparation of suitable nanocarrier based on benchmarked mesoporous iron(III) trimesate nanoparticles coated with bioadhesive polysaccharide chitosan (CS). This...
The growth of the $\sqrt{3} \times \sqrt{3}$ reconstructed silicene on Ag substrate has been frequently observed in experiments while its atomic structure and formation mechanism is poorly understood. Here by first-principles calculations we show that constituted dumbbell units Si atoms arranged a honeycomb pattern. Our model shows excellent agreement with experimentally reported lattice constant STM image. We propose new for explaining spontaneous consequential structures from $3 3$...
Abstract The achievement of the superlubricity regime, with a friction coefficient below 0.01, is Holy Grail many tribological applications, potential to have remarkable impact on economic and environmental issues. Based combined high-resolution photoemission soft X-ray absorption study, we report that can be realized for engineering applications in bearing steel coated ultra-smooth tetrahedral amorphous carbon (ta-C) under oleic acid lubrication. results show tribochemical reactions...
Controlling the outer surface of nanometric metal-organic frameworks (nanoMOFs) and further understanding in vivo effect coated material are crucial for convenient biomedical applications MOFs. However, most studies, modification protocol is often associated with significant toxicity and/or lack selectivity. As an alternative, how highly selective general grafting GraftFast method leads, through a green simple process, to successful attachment multifunctional biopolymers (polyethylene glycol...
The crystallographic stacking order in multilayer graphene plays an important role determining its electronic structure. In trilayer graphene, rhombohedral (ABC) is particularly intriguing, exhibiting a flat band with electric-field tunable gap. Such structure distinct from simple hexagonal (AAA) or typical Bernal (ABA) and promising for nanoscale electronics optoelectronics applications. So far clean experimental spectra on the first two stackings are missing because samples usually too...
New synthesis routes to tailor graphene properties by controlling the concentration and chemical configuration of dopants show great promise. Herein we report direct reproducible 2-3% nitrogen-doped 'few-layer' from a solid state nitrogen carbide a-C:N source synthesized femtosecond pulsed laser ablation. Analytical investigations, including synchrotron facilities, made it possible identify chemistry films. Auger mapping successfully quantified 2D distribution number layers over surface,...
The recent observation of correlated phases in transition metal dichalcogenide moiré systems at integer and fractional filling promises new insight into metal-insulator transitions the unusual states matter that can emerge near such transitions. Here, we combine real- momentum-space mapping techniques to study superlattice effects 57.4° twisted WSe_{2} (tWSe_{2}). Our data reveal a split-off flat band derives from monolayer Γ states. Using advanced analysis, directly quantify potential our...
The Sn/Ge(111) interface has been investigated across the $3\ifmmode\times\else\texttimes\fi{}3\ensuremath{\rightarrow}\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3}R30\ifmmode^\circ\else\textdegree\fi{}$ phase transition using core level and valence band photoemission spectroscopies. We find, both above below transition, two different components in Sn $4d$ a splitting surface state crossing Fermi energy. Theoretical calculations show that these effects are due to existence of...
We report topology of the Fermi surface ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$ superconducting system at optimum doping determined by sequential angle-scanning photoemission combined with high intensity synchrotron radiation. The has a pseudogap around $(\ensuremath{\pi},0)$ as in underdoped samples, showing missing segments near $M$ points, and shadow bands $(0.5\ensuremath{\pi},0.5\ensuremath{\pi})$ equivalent locations. $k$ dependence...
Graphene layers have been grown by molecular beam epitaxy (MBE) on the (0001¯) C-face of SiC and characterized atomic force microscopy, low energy electron diffraction (LEED), UV photoelectron spectroscopy. Contrary to graphitization process, step-terrace structure is fully preserved during MBE growth. LEED patterns show multiple orientation domains which are characteristic graphene (0001¯), indicating non-Bernal rotated planes. Well-defined Dirac cones, typical single-layer graphene,...