Probing Unruh Effect from Enhanced Decoherence

TL;DR

This paper studies how an Unruh-DeWitt detector's decoherence rate in Minkowski spacetime scales with acceleration and field operator dimension, proposing a sensitive method to probe the Unruh effect.

Contribution

It derives a universal scaling law for decoherence rate dependence on acceleration and operator dimension, using the influence functional formalism.

Findings

Decoherence rate scales as $a^{2 riangle-1}$ for long times.

Higher scaling dimension enhances decoherence, improving Unruh effect detection.

Universal relation applies to scalar, electromagnetic, and spinor fields.

Abstract

We investigate the decoherence of an Unruh-DeWitt detector coupled to scalar, electromagnetic, and spinor fields in four-dimensional Minkowski spacetime. By employing the Schwinger-Keldysh influence functional formalism, we derive a universal scaling law relating the decoherence rate to the proper acceleration $a$ and the scaling dimension $\Delta$ of the environmental field operator. By analyzing both sharp (top-hat) and smooth Gaussian switching functions, it is shown that the decoherence rate in the asymptotic long-time limit scales as $a^{2\Delta-1}$. This scaling indicates that increasing scaling dimension of the coupling field operators can significantly enhance the decoherence, thereby providing a more sensitive probe of the Unruh effect.