Konwersatorium im. Leopolda Infelda

Quantum enhanced metrology has seen a tremendous interest in recent years. The use of entangled states allows in principle to beat the shot noise scaling of precision in light and atom interferometry. This might give a precision boost to some of the most ambitious metrological projects such as gravitational wave detectors and atomic clocks. We derive fundamental bounds on the maximal possible quantum enhancement of precision taking into account realistic effects of decoherence. Moreover, we show that when decoherence is present, simple quantum strategies, based on the use of squeezed states of light or atoms, are close to optimal