  We propose a protocol for the amplified detection of low-intensity terahertz
radiation using Rydberg tweezer arrays. The protocol offers single photon
sensitivity together with a low dark count rate. It is split into two phases:
during a sensing phase, it harnesses strong terahertz-range transitions between
highly excited Rydberg states to capture individual terahertz photons. During
an amplification phase it exploits the Rydberg facilitation mechanism which
converts a single terahertz photon into a substantial signal of Rydberg
excitations. We discuss a concrete realization based on realistic atomic
interaction parameters, develop a comprehensive theoretical model that
incorporates the motion of trapped atoms and study the many-body dynamics using
tensor network methods.
