Acceleration-assisted entanglement harvesting and rangefinding

Abstract

We study entanglement harvested from a quantum field through local interaction with Unruh-DeWitt detectors undergoing linear acceleration. The interactions allow entanglement to be swapped locally from the field to the detectors. We find an enhancement in the entanglement harvesting by two detectors with anti-parallel acceleration over those with inertial motion. This enhancement is characterized by the presence of entanglement between two detectors that would otherwise maintain a separable state in the absence of relativistic motion (with the same distance of closest approach in both cases). We also find that entanglement harvesting is degraded for two detectors undergoing parallel acceleration in the same way as for two static, comoving detectors in a de Sitter universe. This degradation is known to be different from that of two inertial detectors in a thermal bath. We comment on the physical origin of the harvested entanglement and present three methods for determining distance between two detectors using properties of the harvested entanglement. Information about the separation is stored nonlocally in the joint state of the accelerated detectors after the interaction; a single detector alone contains none. We also find an example of entanglement sudden death exhibited in parameter space.

Quantum circuit model for non-inertial objects: a uniformly accelerated mirror

“…When one uses a partially transmitting mirror ( q < W cos 1) to sever the correlations across the horizon, local squeezing is inevitably produced according to equation (33). Furthermore, there may be other ways to sever the correlations across the horizon, for example by using two uniformly accelerated Unruh-DeWitt detectors in left and right Rindler wedges [40,41].…”

Precise space–time positioning for entanglement harvesting

“…The vacuum state of a long-range field is unentangled with respect to its extended non-local modes but can be entangled with respect to local modes [1] corresponding to localized detectors. Extracting this naturally endowed resource from a quantum field vacuum via localized detectors, such as atomic probes, is called vacuum entanglement harvesting [2][3][4][5][6]. The process can be understood in the following terms: an actuator turns the interaction between these two detectors and the field on and off, resulting in two initially unentangled detectors evolving into an entangled pair, after ignoring, or tracing out, the field itself.…”

Quantum seismology

“…Further work showed that this entanglement can, in principle, be used to violate Bell inequalities [3]. The amount of entanglement depends on properties of the field, of the background spacetime [4,5] and of the atom trajectories [6].…”