Universality and thermalization in the Unruh Effect

We explore the effects of different boundary conditions and coupling schemes on the response of a particle detector undergoing uniform acceleration in optical cavities. We analyze the thermalization properties of the accelerated detector via non-perturbative calculations. We prove non-perturbatively that if the switching process is smooth enough, the detector thermalizes to the Unruh temperature regardless of the boundary conditions and the form of the coupling considered.