Giant vacuum forces via transmission lines

Abstract

Quantum electromagnetic fluctuations induce forces between neutral particles, known as the van der Waals and Casimir interactions. These fundamental forces, mediated by virtual photons from the vacuum, play an important role in basic physics and chemistry and in emerging technologies involving, e.g., microelectromechanical systems or quantum information processing. Here we show that these interactions can be enhanced by many orders of magnitude upon changing the character of the mediating vacuum modes. By considering two polarizable particles in the vicinity of any standard electric transmission line, along which photons can propagate in one dimension, we find a much stronger and longer-range interaction than in free space. This enhancement may have profound implications on many-particle and bulk systems and impact the quantum technologies mentioned above. The predicted giant vacuum force is estimated to be measurable in a coplanar waveguide line.Casimir physics | quantum vacuum | circuit quantum electrodynamics | dispersion forces T he seminal works of London (1), Casimir and Polder (2), and Casimir (3) identified quantum electromagnetic fluctuations to be the source of both short-range [van der Waals (vdW)] and retarded, long-range (Casimir) interactions between polarizable objects, which may be viewed as an exchange of virtual photons from the vacuum. Subsequent studies of these interactions (4-14) revealed their modifications, such as retardation and nonadditivity (15), brought about by the geometry of the polarizable objects. The ability to design these interactions is important for their possible use and exploration in emerging quantum technologies such as microelectromechanical systems (16), quantum information processing (17, 18), and circuit quantum electrodynamics, where the dynamical Casimir effect has been recently demonstrated (19,20). Here we show that effectively one-dimensional (1D) transmission-line environments can induce strongly enhanced and longer-range van der Waals and Casimir interactions compared with free space. Such enhanced interactions may have profound implications on the quantum technologies mentioned above and give rise to a variety of new many-body phenomena involving polarizable particles in effectively 1D environments.A key point in determining how these interactions depend on distance is the spatial propagation and scattering of the virtual photon modes that mediate them. Like any other waves, photons are scattered differently off objects with different geometries. For example, light is much more effectively scattered off a mirror than off a point-like atom. This explains the stronger and longerrange vacuum interaction between mirrors (3), compared with that between atoms (2). This idea also underlies the dependence of Casimir forces on the geometrical shape of the interacting objects. Here, we take a somewhat different approach toward the geometry dependence of vdW-and Casimir-related phenomena. Instead of considering the interaction energy of extended objects with different ...

van der Waals interactions between excited atoms in generic environments

“…In addition, both the oscillating and monotonous force components are expected to arise in waveguides as recently studied in Refs. [33][34][35][36]. It could be also interesting to generalize our model to include finite temperature, by chancing the fluctuation relations of the electromagnetic field, and to consider many-body vdW forces.…”

Effect of curvature and confinement on the Casimir-Polder interaction

“…(25), (26)), and when the atom is close to the axis of the cylinder (dashed curves, see Eqs. (27), (28)). The thick curves represent the full numerical result for f E cl (δ) (Eq.…”

Casimir forces in transmission-line circuits: QED and fluctuation-dissipation formalisms

“…Quantum vacuum fluctuations of waveguide modes may also drive and mediate novel Casimir and van der Waals forces, with drastically modified distance dependencies [19][20][21][22][23][24][25]. Of particular interest are such vacuum-induced interactions mediated by transmissionline waveguides, which can become extremely long-range and strong [19][20][21], as opposed to e.g.…”

“…Of particular interest are such vacuum-induced interactions mediated by transmissionline waveguides, which can become extremely long-range and strong [19][20][21], as opposed to e.g. exponentially decreasing interactions mediated by other waveguides [22][23][24].…”

“…The first approach considered here is a straightforward adaptation of QED to TL circuits, consisting of canonical quantization of propagating voltage and current fields [30,31]. Quantum fluctuations and associated phenomena then originate in those quantized fields, and are described by an effective 1d QED theory, combined with a 1d scattering formalism [19,32].…”