Quantum Nondemolition Measurements in Quantum Optics

Philippe Grangier

Ulrik L. Andersen, B. C. Buchler, Ping Koy Lam +2 more

Quantum Nondemolition (QND) measurements are carried out using a stable amplitude squeezed beam. The performance of the QND measurement is substantially enhanced by an electro-optic feedforward loop, which improves the signal transfer efficiency.

J.-Ph. Poizat, Jean-François Roch, Philippe Grangier

Guoxi Fang, Yancheng Zhao

In this paper, the method will be introduced, it's called Quantum Nondemolition measurement. The purpose is to realize a new measuring method to surpass quantum limit. It provides a new method of overcoming quantum noise. In principle, it can use any precision to detect a certain weak signal. Finally, the application of QND Measurement in optical communication will be introduced.

Victor V. Kozlov

Hans‐A. Bachor, M. D. Levenson, Daniel F. Walls +2 more

A quantum nondemolition (QND) measurement scheme utilizing a Kerr medium enclosed in a resonant cavity is described and analyzed theoretically. The theory demonstrates that the conditions for QND can be met in such a device. An experimental realization in the form of an optical-fiber ring resonator has been constructed and initial experimental results are presented.