We propose and analyze an experiment in which atoms in a coherent superposition of atomic states are injected into a high-Q maser cavity. We show that the symmetry of the field in the cavity is ‘‘broken’’ in the same way as results from a classical signal injected into a laser cavity. This broken symmetry can be detected by monitoring the atomic excitation of a probe atom.

• Received 24 February 1986

DOI:https://doi.org/10.1103/PhysRevA.34.2032