Charged Unruh effect on geon spacetimes

A topological geon black hole with gauge charges may have a gauge bundle that necessarily incorporates charge conjugation as a gauge symmetry. This happens for example for the Reissner-Nordstrom geon. We show that gauging the charge conjugation leaves an imprint in the Unruh effect: the geon's exterior region contains non-thermal correlations for particle pairs of the same, rather than opposite, charge. The phenomenon occurs also in topologically similar Rindler spacetimes with a background gauge field.Comment: 3 pages, talk given by David E. Bruschi at the 12th Marcel Grossmann Meetin

Thermodynamics of relativistic quantum fields confined in cavities

We investigate the quantum thermodynamical properties of localised relativistic quantum fields, and how they can be used as quantum thermal machines. We study the efficiency and power of energy transfer between the classical gravitational degrees of freedom, such as the energy input due to the motion of boundaries or an impinging gravitational wave, and the excitations of a confined quantum field. We find that the efficiency of energy transfer depends dramatically on the input initial state of the system. Furthermore, we investigate the ability of the system to extract energy from a gravitational wave and store it in a battery. This process is inefficient in optical cavities but is significantly enhanced when employing trapped Bose Einstein condensates. We also employ standard fluctuation results to obtain the work probability distribution, which allows us to understand how the efficiency is related to the dissipation of work. Finally, we apply our techniques to a setup where an impinging gravitational wave excites the phononic modes of a Bose Einstein condensate. We find that, in this case, the percentage of energy transferred to the phonons approaches unity after a suitable amount of time. These results give a quantitative insight into the thermodynamic behaviour of relativistic quantum fields confined in cavities.Comment: 35 pages, 3 figures. Manuscript substantially updated. I. Fuentes also published as I. Fuentes-Guridi and I. Fuentes-Schulle

Entanglement generation in relativistic cavity motion

We analyse particle creation and mode mixing for a quantum field in an accelerated cavity, assuming small accelerations but allowing arbitrary velocities, travel times and travel distances, and in particular including the regime of relativistic velocities. As an application, we identify a desktop experimental scenario where the mode mixing resonance frequency in linear sinusoidal motion or in uniform circular motion is significantly below the particle creation resonance frequencies of the Dynamical Casimir Effect, and arguably at the threshold of current technology. The mode mixing acts as a beamsplitter quantum gate, experimentally detectable not only via fluxes or particle numbers but also via entanglement generation.Comment: 8 pages, LaTeX with jpconf. Submitted to DICE2012 proceeding

Gravity-induced electric currents

We study the generation of an electric current in an ideal conducting coil, immersed in a magnetic field, due to the occurrence of a gravitational perturbation. We show that this effect can be used to detect gravitational waves impinging on the coil as well as gravitational gradients when the coil moves in a static background gravitational field. Our work opens the way to employing induced electric signals to detect dynamical gravitational fields and for gradiometry.Comment: 11 pages, 4 figure