Quantum computing with a hybrid array of molecules and Rydberg atoms
Domaines
Quantum optics/Atomic physics/Laser
Quantum information theory and quantum technologies
Quantum optics
Quantum gases
Type de stage
Expérimental
Description
Quantum computing requires precise control of individual quantum systems and their interactions. Ultracold molecules offer long-lived quantum states for storing information, while Rydberg atoms provide strong interactions for fast quantum operations. Combining these advantages opens a new route towards scalable quantum computing.
Our group is developing an experimental platform combining individual CaF molecules and Rb atoms in reconfigurable optical tweezer arrays. The long-term goal is to exploit molecule–Rydberg atom interactions to implement fast quantum gates and new methods for manipulating and measuring molecular qubits.
During this six-month internship, the student will contribute to the development and characterisation of the hybrid experimental platform. Depending on experimental progress and the student's interests, the work may focus on optical tweezer generation and control, single-particle trapping and imaging, Rydberg excitation, or the development of experimental control and data analysis techniques. The student will work closely with researchers developing this new quantum computing platform.
Effets mémoire dans les solides désordonnés : Étude expérimentale sur des matériaux polymères.
Domaines
Statistical physics
Soft matter
Nonequilibrium statistical physics
Type de stage
Expérimental
Description
Dans les systèmes désordonnés, l’état du matériau dépend de façon cruciale et fortement non évidente de l’histoire du système. Sur des matériaux aussi divers que des amorphes vitreux comme les verres ou les polymères, des gels simples ou complexes, mais aussi des textiles, on retrouve cette capacité du matériau à garder en mémoire, au moins un certain temps, l’histoire des contraintes mécaniques, thermiques, chimiques... qu’il a subi. Nous nous intéressons plus particulièrement à la façon d’écrire, de lire et d’effacer cette mémoire des matériaux désordonnés.
Nous proposons donc d’utiliser la machine de traction développée au Laboratoire de Physique à l'ENS de Lyon, pour réaliser des cycles de traction - relâchement jusqu’à une déformation maximale fixée, suivis de lectures à des déformations de plus en plus grandes, de façon à caractériser ces effets mémoire et leur lien avec la dynamique des chaines de polymères.
Controlling the polarization of light with chiral plasmonic nanostructures
Domaines
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type de stage
Expérimental
Description
In this project we will (1) locally and electrically excite chiral plasmonic nanoparticles and (2) to use them to enhance the chiral properties of a new class of two-dimensional (2D) semiconductors called transition metal dichalcogenides (TMDCs), which are key for a new branch of physics and technology called valleytronics
Transverse spreading of 2D localized microwaves in the presence of absorption
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Statistical physics
Low dimension physics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type de stage
Expérimental et théorique
Description
Various mechanisms underlie metal-insulator transitions in condensed matter. One of these mechanisms is Anderson localization, which is caused by quantum interference induced by disorder. As a consequence, the Drude diffusion of an electron through the sample has to be corrected, and when the interferences become large enough, conduction may cease, leading to an insulating phase. Because the origin of this phenomenon lies in interference, it has been suggested 40 years ago by Anderson himself that it should be easily observed using "classical" waves as light or sound. A signature of localization lies in the transmission transverse profile: in the diffusion regime, a Gaussian beam spreads in time whereas in the localization regime it saturates. This transverse profile beam spreading should be independent of transmission.
The intern will perform an experimental test of the independence of the claim that the transverse profile spreading in the presence of Anderson localization does not depend on absorption.
Critical scaling of the bandgap appearance in 2D disordered photonic materials
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Statistical physics
Low dimension physics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type de stage
Théorique, numérique
Description
Historically, photonic crystals and the concept of photonic bandgap were introduced in the seminal works of Yablonovitch and John in the 1980s. Even if natural examples exists (for instance in the blue iridescent wings of the Morpho butterfly), the first experimental realizations were done in the microwave regime by drilling holes in epoxy resin, and over the last 15 years, significant progresses in the micro and nano fabrication have been achieved enabling the availability of 3D materials with gaps or pseudo-gaps in the near-infrared. Nevertheless, despite a considerable amount of work reporting the measurement of photonic band gaps in different regimes (optical, infrared or microwave), an explanation of when to expect or not to expect a band gap is still lacking. Furthermore, even when a bandgap does exist, it is unclear exactly at which frequency it will occur and how wide it will be.
Using bandgap computation to compute the bandgap frequency and width fluctuations in two-dimensional hyperuniform dielectric materials, we propose to explore the idea of a possible continuous phase transition in the appearance of the bandgap using finite size scaling.