Nonthermal effects of acceleration in the resonance interaction between two uniformly accelerated atoms

Abstract

We study the resonance interaction between two uniformly accelerated identical atoms, one excited and the other in the ground state, prepared in a correlated (symmetric or antisymmetric) state and interacting with the scalar field or the electromagnetic field in the vacuum state. In this case (resonance interaction), the interatomic interaction is a second-order effect in the atom-field coupling. We separate the contributions of vacuum fluctuations and radiation reaction to the resonance energy shift of the system, and show that only radiation reaction contributes, while Unruh thermal fluctuations do not affect the resonance interaction. We also find that beyond a characteristic length scale related to the atomic acceleration, non-thermal-like effects in the radiation reaction contribution change the distance-dependence of the resonance interaction. Finally, we find that previously unidentified features appear, compared with the scalar field case, when the interaction with the electromagnetic field is considered, as a consequence of the peculiar nature of the vacuum quantum noise of the electromagnetic field in a relativistically accelerated background.

Resonance interaction energy between two accelerated identical atoms in a coaccelerated frame and the Unruh effect

“…Following the procedure of Dalibard et al [53,54] to separate vacuum fluctuations and radiation reaction contributions, we calculate the resonance interaction between two atoms prepared in a correlated state, and interacting with the scalar or the electromagnetic field in the vacuum state (in the Rindler frame). In agreement with the results in [44], we show that vacuum field fluctuations do not affect the resonance interaction between the two correlated atoms, which is exclusively due to the radiation reaction contribution. In both cases considered (scalar and electromagnetic field) we obtain in the coaccelerated frame the same expressions of the resonance interaction obtained in the comoving frame, without any additional assumption of an Unruh temperature for the quantum field.…”

“…It has been shown that Unruh thermal fluctuations do not affect the resonance interaction between the two accelerated atoms, which is exclusively due to the radiation reaction field. Nevertheless, the noninertial motion of the atoms affects the resonant interatomic energy, showing new properties, ultimately related to the peculiar structure of the quantum vacuum of the electromagnetic field in a locally inertial frame [44]. In particular, nonthermal effects of the atomic acceleration, related to the noninertial character of accelerated motion, result in a different scaling with the distance and a different dependence on the acceleration compared to those expected from the known Unruh acceleration-temperature equivalence.…”

“…Then, the time evolution of a generic atomic observable can be split in the sum of free and source contributions. Similarly as in [24,44], we find that the time evolution of a generic atomic observable, pertaining, for example, to atom A, can be described in terms of two effective Hamiltonians, (H ef f A ) vf (related to vacuum field fluctuations) and (H ef f A ) rr (related to the radiation reaction field). We get…”

“…The relation of the resonance interaction with other physical processes, such as the resonant energy transfer [47], as well as its role in some coherent biological processes [52], have been also investigated. Also, very recently the resonance interaction between two uniformly accelerated atoms in the Minkowski space has been investigated from the point of view of a comoving frame [44]. It has been shown that Unruh thermal fluctuations do not affect the resonance interaction between the two accelerated atoms, which is exclusively due to the radiation reaction field.…”

“…The resonance interaction between uniformly accelerated atoms in the Minkowski vacuum has been recently investigated in the comoving frame [44]. Also, the radiative properties of uniformly accelerated entangled atoms have been recently investigated [45].…”