Researcher Publishes Comprehensive Study on Atomic Structure and Molecular Interactions in Ultracold Systems
Physicist Maxence Lepers of CNRS and the University of Burgundy has posted a 188-page habilitation thesis on arXiv covering atomic-structure calculations and long-range interactions in ultracold gases and rare-earth doped solids. The work spans two main themes: electronic structure of neutral and trivalent lanthanide atoms, and long-range interaction potentials relevant to alkali-metal and lanthanide ultracold systems. These results bear on ultralow-temperature phenomena such as photoassociation and collisional shielding, which are central to quantum gas research and quantum technology applications.
Maxence Lepers, a researcher at the Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB, CNRS/University of Burgundy), has submitted his Habilitation à diriger des recherches (HDR) manuscript to arXiv, summarizing his post-doctoral research program. The 188-page document, containing 43 figures, is organized into two parts: the first addresses atomic-structure calculations for neutral and trivalent lanthanide atoms in the contexts of ultracold gases and rare-earth doped optical materials; the second systematically treats long-range interaction potentials in ultracold gases of alkali-metal atoms, diatomic molecules, and lanthanide atoms. Long-range interactions—typically van der Waals and dipole-dipole forces—govern collision dynamics and bound-state formation at ultralow temperatures, making their precise characterization essential. The thesis connects these calculations to experimentally observable phenomena including photoassociation spectroscopy and collisional shielding strategies used to suppress inelastic losses in molecular quantum gases. The manuscript was first submitted in November 2025 and revised through June 2026, indicating ongoing refinement prior to formal evaluation.
What's missing
As an HDR manuscript rather than a peer-reviewed journal article, the work has not yet undergone formal external peer review at the time of arXiv posting. The abstract does not specify which theoretical methods (e.g., relativistic configuration interaction, coupled-cluster) were employed, nor does it detail the quantitative accuracy benchmarks achieved relative to experimental data.
What different sources said
- arXiv physicsCenter
Structure and interactions of atoms and diatomic molecules: from ultracold gases to doped solids
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