Documents de présentation
The ever-increasing demand of information technology for power-efficient components has led to the search for alternative solutions to mainstream microelectronics. In this context, spintronics devices stand out as competitive candidates, especially for memory and logic applications. A promising route harvests unconventional transport properties arising from spin-orbit coupling in magnetic...
Spin-orbitronics is a wide field that takes advantage of the effect of spin-orbit coupling (SOC) on the spintronic response of materials. SOC is the responsible for the spin-charge interconversion through effects such as Edelstein effect, which occurs naturally in topological insulators and Rashba systems. One recently proposed spin-orbitronic device is the Magnetoelectric Spin-Orbit (MESO)...
Dans cet exposé nous présenterons des résultats expérimentaux et théoriques récents de photoémission de basse énergie sur un échantillon de GaN dopé p à affinité électronique négative. Nous discuterons dans un premier temps de divers types de transitions, telles que la transition Franz-Keldysh et l'émission depuis des défauts, contribuant au rendement quantique pour des excitations d'énergie...
Oxide heterostructures are regarded as promising platforms for the next generation of electronic devices, displaying straightforward properties like high carrier mobility to exotic functionalities like multiferroicity. In polar heterostructures, the interfacial electric field can produce a two dimensional electron gas (2DEG). The broken inversion symmetry results in Rashba spin-orbit coupling...
The persistence of a magnetic order in a monolayer of van der Waals magnetic material has been established in 2016, offering the perspective to embed a magnetic degree of freedom in heterostructures made of other bidimensional materials such as graphene or light-emitting transition metal dichalcogenides. The physical properties of van der Waals materials can be easily tuned by perturbations...
Two-dimensional heterostructures can be built very efficiently by directly stacking individual monolayers of different 2D materials. Their wide range of functionality allows for applications spanning from tunneling transistors to optoelectronic devices. In order to control the final performance of these systems, it is fundamental to understand how the electronic properties of each layer are...
Since several years, the domain of molecular spintronics focuses on the insertion of molecules in spin valve devices. Different studies underlined the crucial role of the interfaces in such kind of devices. To go towards controllable interfaces with external stimuli, spin-crossover molecules are particularly promising as they present two spin states (a high spin state and a low spin state)...
Charge density waves (CDWs) occur in many solids, in particular, in layered materials like transition metal dichalcogenides (TMDs). In bulk 1T-VSe2 the charge density modulation is known to be 4x4x3 with a 4x4 in-plane periodicity and three times the lattice vector out of the plane. However, for the monolayer or Na-intercalated VSe2 the CDW periodicity in the plane becomes √3R30x√7R19 [1]....
The interface between a liquid and a solid is the location of plethora of intrincate mechanisms at the nanoscale, at the root of their specific emerging properties in natural processes or technological applications. However, while the structural properties and chemistry of interfaces have been intensively explored, the effect of the solid-state electronic transport at the fluid interface has...
Carbon nanotubes (CNTs) are outstanding materials with very particular mechanical, thermal and electrical properties due to their sp²-hybridization resulting in nearly perfect atomic structures. Two other properties of CNTs are their lightness since their mass are in the range of the attogram (1 ag = 10-18 g) and their defect-free surfaces. CNTs are synthesized using bottom-up methods which...
The future sparsity of carbon-based fuels, the increasing energy cost, together with the growing concern of society over environmental problems, make the performance improvement of energy conversion devices – thermoelectricity, photovoltaics – a topic of high importance. Such devices are mainly designed by using macroscopic models -the drift-diffusion for electronic transport, or the Fourier...
