Patent attributes
An electromagnetic field detector including a vapor cell, an excitation system, and a frequency tuner is described. The vapor cell has a plurality of quantum particles therein. The excitation system excites the quantum particles to a first Rydberg state. The first Rydberg state has a transition to a second Rydberg state at a first frequency. The frequency tuner generates a tunable field in a portion of the vapor cell. The tunable field shifts the first Rydberg state and/or the second Rydberg state such that the transition to the second Rydberg state is at a second frequency different from the first frequency. The detection frequency range for the electromagnetic field detector is continuous and includes the first frequency and the second frequency.