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arXiv · 1404.5621

Particle detectors and the zero mode of a quantum field

Eduardo Martin-Martinez·Jorma Louko
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Abstract

We study the impact of the zero-mode of a quantum field on the evolution of a particle detector. For a massless scalar field in a periodic cavity, we show that the impact of the zero mode on the Unruh-DeWitt detector and its derivative-coupling generalisation is necessarily nonvanishing but can be made negligible in some limits, including those commonly occurring in non-relativistic quantum optics. For the derivative-coupling detector this can be accomplished by just tuning the zero mode's initial state, but the standard Unruh-DeWitt detector requires a more subtle and careful tuning. Applications include an inertial detector with arbitrary velocity, where we demonstrate the regularity of the ultrarelativistic limit, and a detector with uniform acceleration.

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Eduardo Martin-Martinez, Jorma Louko. 2014-07-10. Particle detectors and the zero mode of a quantum field. https://doi.org/10.1103/physrevd.90.024015

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