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Multipole blackbody radiation shift of Rydberg energy levels

R. M. Potvliege*

  • *Contact author: r.m.potvliege@durham.ac.uk
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Phys. Rev. A 114, 032816 – Published 14 September, 2026

DOI: https://doi.org/10.1103/8s3y-pqbd

Abstract

We study the role of retardation in the energy shift of Rydberg states induced by thermal radiation, focusing on the case of temperatures higher than those for which the electric dipole approximation is expected to apply. As anticipated by Farley and Wing [J. W. Farley and W. H. Wing, Phys. Rev. A 23, 2397 (1981)], retardation needs to be taken into account in calculations of this energy shift around and above the temperature αmc2/(3kBn2), where n is the principal quantum number of the state considered, m is the mass of the electron, and kB is the Boltzmann constant, e.g., around and above 1440 K for n=100. The corresponding nondipole shift dominates the electric dipole shift at about 2.5 times that characteristic temperature. Thermal shifts arising from retardation and from the electric quadrupole interaction are of the same order of magnitude as the diamagnetic thermal shift and would thus need to be taken into account in the circumstances where the latter is relevant.

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References (31)

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Phys. Rev. A 114, 032816– Published 14 September, 2026
  • Received 10 June 2026
  • Accepted 28 August 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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