Detectable Signature of Quantum Friction on a Sliding Particle in Vacuum

Abstract

Spatially separated bodies in a relative motion through vacuum experience a tiny friction force known as quantum friction (QF). This force has so far eluded experimental detection due to its small magnitude and short range. Quantitative details revealing traces of the QF in the degradation of the quantum coherence of a particle are presented. Environmentally induced decoherence for a particle sliding over a dielectric sheet can be decomposed into contributions of different signatures: one solely induced by the electromagnetic vacuum in the presence of the dielectric and another induced by motion. As the geometric phase (GP) has been proved to be a fruitful venue of investigation to infer features of the quantum systems, herein it is proposed to use the accumulated GP acquired by a particle as a QF sensor. Furthermore, an innovative experiment designed to track traces of QF by measuring the velocity dependence of corrections to the GP and coherence is proposed. The experimentally viable scheme presented can spark renewed optimism for the detection of non‐contact friction, with the hope that this non‐equilibrium phenomenon can be readily measured soon.

Motion-Induced Radiation Due to an Atom in the Presence of a Graphene Plane

“…Dividing Equations ( 57) and (56), and taking into account Equation (58), we see that a necessary condition for friction to happen is v ≥ v F . The situation considered here is more interesting for an eventual experimental observation of the effect, because frictional effects only exist if the speed of the sliding motion is larger than the Fermi velocity of the charge carriers in graphene, a condition that is more easily achieved for an atom than for a whole sheet (for example, for the implementation of the experimental proposal in [33]). There is no dissipative effect until u > v F = 0.003, and QF increases as the parallel speed of the atom grows.…”

“…It has also been shown that QF could influence the coherences of a two-level atom [32]. Furthermore, an innovative experiment was designed to track traces of QF by measuring this corrections to the geometric phase [33]. This experimentally viable scheme can spark, we believe, hope for the detection of noncontact friction.…”

Sensing quantum chaos through the non-unitary geometric phase

“…We remark that in the past the task of sensing with a probe a certain property of a many-body quantum system has already been demonstrated in the literature, both theoretically and experimentally, for identifying critical points, phase transitions, unknown temperatures and non-Markovian behaviour [19][20][21][22]. In those works, a common approach that has already proven its worth is to monitor how the geometric phase acquired by the probe is corrected due to its coupling to the many-body environment with respect to its unitary evolution [23][24][25][26][27][28][29].…”

Quantum Vacuum Sagnac Effect

“…In the context of atom interferometry, a nonlocal phase associated with pairs of paths (rather than with individual ones) was shown to result from the field-mediated interaction between a moving atom and a material surface [27][28][29]. Dynamical Casimir emission of photons [30][31][32][33][34], decoherence [35,36] and quantum friction [37][38][39][40][41][42][43] also result from the coupling between a moving atom and the quantum electromagnetic field. Given their high sensitivity, atom interferometers are candidates for the first experimental demonstration of motional effects in Casimir physics, and the QVSP would be particularly appealing for that purpose.…”

“…In this sense, it constitutes a dynamical Casimir-like effect. However, as a nanoparticle spinning at constant velocity produces no radiation [24,25], the QVSP does not rely on the presence of real dynamical Casimir photons -nor does it rests on open-quantum system dynamics [52] responsible for quantum friction [41,43].…”