Motion induced radiation and quantum friction for a moving atom

LOMBARDO, FERNANDO C.; FOSCO, C. D.; FARÍAS, M. BELÉN; MAZZITELLI, FRANCISCO D.

Physical Review D

Americal Physical Society

Lugar: New York; Año: 2019 vol. 100 p. 360131 - 3601313

2470-0010

We study quantum dissipative effects that result from the non-relativistic motion of an atom,coupled to a quantum real scalar field, in the presence of a static imperfect mirror. Our studyconsists of two parts: in the first, we consider accelerated motion in free space, namely, switchingoff the coupling to the mirror. This results in motion induced radiation, which we quantify via thevacuum persistence amplitude. In the model we use, the atom is described by a quantum harmonicoscillator (QHO). We show that its natural frequency poses a threshold which separates differentregimes, involving or not the internal excitation of the oscillator, with the ulterior emission of aphoton. At higher orders in the coupling to the field, pairs of photons may be created by virtueof the Dynamical Casimir Effect (DCE). In the second part, we switch on the coupling to themirror, which we describe by localized microscopic degrees of freedom. We show that this leadsto the existence of quantum contactless friction as well as to corrections to the free space emissionconsidered in the first part. The latter are similar to the effect of a dielectric on the spontaneousemission of an excited atom. We have found that, when the atom is accelerated and close to theplate, it is crucial to take into account the losses in the dielectric in order to obtain finite results forthe vacuum persistence amplitude.