STAGE Optical studies of 2D-0D heterostructures

Date de mise à jour de l’offre

LuMIN: Lumière, Matière et Interfaces :

Ce nouveau laboratoire a l’ambition de faire rayonner dans l’environnement stimulant du plateau de Saclay des thématiques dont le socle commun est la photonique, mais dont la particularité est de se situer à l’interface de nombreux autres champs, comme la chimie, la biologie, le biomédical, les sciences de l’ingénieur, les nanosciences, la microfluidique, etc. LuMIn se divise en deux axes présentant des projets originaux et très ambitieux, l’un tourné vers la photonique du vivant, fortement positionné dans l’interdisciplinarité avec la biologie, l’autre centré sur l’interaction lumière-matière, regroupant aussi des équipes de premier niveau international sur un panel large de thématiques.

Description de la mission

For almost a decade the science of 2D materials beyond graphene, such as transition metal dichalcogenides (TMDCs) or hexagonal boron nitride (h-BN), has been developing a lot. On one hand, h-BN is an insulator with a bandgap around 6eV, a low chemical reactivity and an almost absence of free dangling bonds and charge traps that make it a quasi-ideal materials to encapsulate other 2D materials. On the other hand, TMDCs are 2D semiconductors with Vis-NIR band gap. The huge spinorbit coupling and the valley asymmetry are good tools for quantum devices where either spin or momentum can be used as information storage.
Scientists have explored the fabrication of 2D heterostructures with the aim of combining the properties of different layered materials. Several combinations have been built with a wide range of objectives both from very fundamental to applied devices point of view. For instance, h-BN has been used to encapsulate graphene. In this configuration, the graphene band structure is almost not perturbed by the h-BN layers and the mobility of this graphene device is greatly increased . Among numerous studies, one can also cites the rich excitonic physics in TMDCs and TMDCs heterostructures. From devices point of view these heterostructures have been used to build photodetectors, photovoltaic cells and light emitting diodes . These combinations of layered materials are very promising and are still widely studied. Nevertheless, the number of combinations is not infinite and there is plenty of room to combine other type of objects with these layered materials. In this perspective, graphene quantum dots (GQDs) can play a major role. Indeed, these 0D pieces of graphene offer a very wide variety of properties related to their size, shape and nature of their edges. Their “bottom-up synthesis ensures an atomic control of the structure leading to a precise control of their properties. A lot of structures have already been synthesized by our chemist colleagues creating a large playground for physicists.
Moreover, their hexagonal planar lattice is compatible with the one of most of the layered materials described above. Recently, we reported on the study of single GQDs by means of micropholtoluminescence experiments [5]. We showed that GQDs can be stable and very bright quantum emitters. Moreover, we proposed a description of the emitting quantum states through spectroscopy measurements. This study demonstrates that the intrinsic properties of GQDs are attractive.

Profil recherché

Experimentalist. Master in « Light-Matter interaction », Master in Condensed Matter, Master in
Quantum Physics

Niveau de qualification requis

Bac + 4/5 et +
  • Employeur
    LuMIN: Lumière, Matière et Interfaces
  • Secteur d’activité de la structure
    Enseignement - Formation - Recherche
  • Effectif de la structure
    De 21 à 50 salariés
  • Type de stage ou contrat
    Stage pour lycéens et étudiants en formation initiale
  • Date prévisionnelle de démarrage
  • Durée du stage ou contrat
    Plus de 4 mois et jusqu'à 6 mois
  • Le stage est-il rémunéré ?
    Oui
  • Niveau de qualification requis

    Bac + 4/5 et +
  • Lieu du stage
    520 building on the Orsay campus
    91400 ORSAY
  • Accès et transports
    RER B ; Bus