Renormalized Unruh-DeWitt Particle Detector Models for Boson and Fermion Fields

Understand

Since quantum field theories do not possess proper position observables, Unruh-DeWitt detector models serve as a key theoretical tool for extracting localized spatio-temporal information from quantum fields.

• Most studies have been limited, however, to Unruh-DeWitt (UDW) detectors that are coupled linearly to a scalar bosonic field.
• Here, we investigate UDW detector models that probe fermionic as well as bosonic fields through both linear and quadratic couplings.
• In particular, we present a renormalization method that cures persistent divergencies of prior models.