Quantum measurement with recycled photons

Abstract

We study a device composed of an optical interferometer integrated with a ferri-magnetic sphere resonator (FSR). Magneto-optic coupling can be employed in such a device to manipulate entanglement between optical pulses that are injected into the interferometer and the FSR. The device is designed to allow measuring the lifetime of such macroscopic entangled states in the region where environmental decoherence is negligibly small. This is achieved by recycling the photons interacting with the FSR in order to eliminate the entanglement before a pulse exits the interferometer. The proposed experiment may provide some insight on the quantum to classical transition associated with a measurement process.