We present a simple scheme for the fast and efficient generation of quantum superpositions of two coherent fields with different classical amplitudes in a cavity. It relies on the simultaneous interaction of two two-level systems with the field. Their final detection with a high probability in the proper state projects the field onto the desired mesoscopic field state superposition. We show that the scheme is notably more efficient than those using a single atom. We discuss the method in the context of microwave cavity quantum electrodynamics, but it is also highly relevant for the thriving field of circuit QED. It may lead to interesting experimental studies of decoherence at the quantum-classical boundary.

• Received 17 November 2014

DOI:https://doi.org/10.1103/PhysRevA.91.013815