Localized projective measurement of a quantum field in non-inertial frames

Abstract

We propose a projective operator formalism that is well-suited to study the correlations of quantum fields in non-inertial frames. We generalise a Glauber model of detection of a single localised field mode that is capable of making measurements in an arbitrary reference frame. We show that the model correctly reproduces the Unruh temperature formula of a single accelerated detector, and use it to extract vacuum entanglement by a pair of counter-accelerating detectors. This latter example is a proof of principle that this approach will be appropriate to further studies on the nature of entanglement in non-inertial frames and, in general, to model experimentally feasible scenarios in quantum field theory in non-inertial frames. Finally, as further confirmation of the validity of our approach, we introduce an explicit perturbative matter-radiation interaction model which reproduces both the generalised Glauber model and the projective measurement results in the weak coupling regime. arXiv:1203.0655v2 [quant-ph] 1 Dec 2012

Continuous variable methods in relativistic quantum information: characterization of quantum and classical correlations of scalar field modes in noninertial frames

“…Interesting approaches to overcome these theoretical and practical limitations, which are now surfacing in RQI literature, include the application of quantum Shannon theory to characterise the communication capacity associated to relativistic channels [23], the study of entanglement between field modes confined in cavities undergoing general spacetime trajectories [21], the analysis of localised observables as detected in different reference frames for directional quantum communication [24], and novel models of localised field and particle detectors [44,45]. Crucially, in most of the above settings, mutatis mutandis one ends up dealing with Gaussian states and transformations.…”

“…Surely, translating the results obtained in this scenario to carry out real experiments is not straightforward at all, and more refined approaches should thus be adopted. Here we limit ourselves to mention some recent proposals regarding localised projective measurements [44] and particle detector models [45], deferring the discussion to the concluding section for additional remarks.…”

Nonmonotonic entanglement of physical electromagnetic field states in noninertial frames

“…Previous results considered tailored families of states which greatly simplified calculations but whose physical interpretation was not clear. Recently, [5] introduced a projective detector model which constitutes a promising new approach to the issue of field entanglement in non-inertial frames. It was shown in [5] that such detectors present the expected thermal response to the inertial vacuum state of the field (i.e.…”

“…Recently, [5] introduced a projective detector model which constitutes a promising new approach to the issue of field entanglement in non-inertial frames. It was shown in [5] that such detectors present the expected thermal response to the inertial vacuum state of the field (i.e. the Unruh effect [6]) and the model provides a good effective description of particle detection.…”

“…There are, however, two different approaches to use the projective model introduced in [5]. Here, we will develop a technique to analyse states by working out the Bogoliubov transformations and the change of basis inertialaccelerated modes in some approximate but physically feasible scenario.…”