Velocity-dependent dipole forces on an excited atom

Abstract

We present a time-dependent calculation of the velocity-dependent forces which act on an excited atomic dipole in relative motion with respect to ground state atoms of a different kind. Both, its interaction with a single atom and with a dilute atomic plate are evaluated. In either case, the total force consists of a conservative van der Waals component and a non-conservative Rontgen component. On physical grounds, the former corresponds to the velocity-dependent recoil experienced by the excited atom in the processes of absorption and emission of the photons that it exchanges with the ground state atoms on a periodic basis. The latter corresponds to the time-variation of the Rontgen momentum, which is also mediated by the periodic exchange of quasi-resonant photons. We find that, at leading order, all these interactions are linear in the velocity. In the non-retarded regime the van der Waals force dominates, being antiparallel to the velocity. On the contrary, in the retarded regime the velocity-dependent forces oscillate in space, van der Waals and Rontgen forces are of the same order in the atom-atom interaction, and the Rontgen component dominates in the atom-surface interaction.

Minor corrections made to agree with the published version

References in corpus (5)

• No quantum friction between uniformly moving plates
• Friction forces on atoms after acceleration
• Quasi-resonant van der Waals interaction between non-identical atoms
• Quantum field theory of the van der Waals friction
• Transfer of linear momentum from the quantum vacuum to a magnetochiral molecule

Cited by in corpus (8)

• The Reality of Casimir Friction
• Quantum Vacuum Sagnac Effect
• Violation of the action-reaction principle in an asymmetrically excited system
• Casimir forces and quantum friction of finite-size atoms in relativistic trajectories
• Two-atom van-der-Waals forces with one atom excited: the identical atoms limit I
• Nonconservative dipole forces in a two-atom system with one atom excited
• Nonreciprocal and nonconservative forces on binary systems of identical atoms
• Microscopic Quantum Friction