Long-range tails in van der Waals interactions of excited-state and ground-state atoms

U. Jentschura, V. Debierre

Research output: Contribution to journalArticle

11 Citations (Scopus)


A quantum electrodynamic calculation of the interaction of an excited-state atom with a ground-state atom is performed. For an excited reference state and a lower-lying virtual state, the contribution to the interaction energy naturally splits into a pole term and a Wick-rotated term. The pole term is shown to dominate in the long-range limit, altering the functional form of the interaction from the retarded 1/R7 Casimir-Polder form to a long-range tail - provided by the Wick-rotated term - proportional to cos[2(Em-En)R/(c)]/R2, where Em<En is the energy of a virtual state, lower than the reference-state energy En, and R is the interatomic separation. General expressions are obtained which can be applied to atomic reference states of arbitrary angular symmetry. Careful treatment of the pole terms in the Feynman prescription for the atomic polarizability is found to be crucial in obtaining correct results.

Original languageEnglish
Article number042506
JournalPhysical Review A
Issue number4
Publication statusPublished - Apr 12 2017

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Fingerprint Dive into the research topics of 'Long-range tails in van der Waals interactions of excited-state and ground-state atoms'. Together they form a unique fingerprint.

  • Cite this