Moments angulaires dans la photoionisation chirale

CELIA est un laboratoire de recherche de l'Université de Bordeaux. Voir www.celia.u-bordeaux.fr.

Un stage pour Master2 (ou équivalent) est disponible au laboratoire CELIA de l'Université de Bordeaux (www.celia.u-bordeaux.fr). Il concerne l'étude théorique de molécules chirales.

Résumé en anglais:

Chiral molecules are of paramount importance in biology because they are building blocks of organic matter, including human beings. Chiral molecules appear in pairs of left- and right-handed enantiomers, where their nuclear arrangements present non-superimposable mirror twins. It is of paramount importance to distinguish the enantiomers since they interact differently with their environment as soon as this latter presents a chiral character, which is the case of most chemoreceptors of living organisms. Enantiomers are generally identified through their interaction with circularly polarized light carrying spin s=±ℏ . Beyond the usual circular dichroism related to the different absorptions of ±ℏ  spin photons, a larger chiral response appears in the photoelectron angular distribution resulting from the ionization of enantio-pure chiral samples [1]. However, we actually know how to generate light pulses which carry orbital angular momentum l=±nℏ  additionally to s . It has recently been shown that such pulses can be employed to control the magnitude of the strong-field ionization probability in atomic and molecular systems [2]. It is therefore likely that the angular momentum of light should also allow to enhance the discrimination of enantiomers through momentum exchange between between light and matter.

This will be theoretically studied in the framework of the internship, focusing of the angular distribution of the photoelectrons, beyond [2].

Les candidats peuvent soumettre leur candidature en ligne ou par mail à Bernard Pons.

Une thèse est prévue après le stage.

Les financements pour le stage et la thèse sont déjà disponibles.

Références:

[1] S. Beaulieu et al., New. J. Phys. 18, 102002 (2016) ; V. Wanie et al., Nature 630, 109 (2024) 

[2] J.-L Bégin et al, https://doi.org/10.21203/rs.3.rs-4768665/v1

Etudiant Master 2 ou équivalent