arXiv:1607.00130 · Physical Review Letters

Reduction of Classical Measurement Noise via Quantum-Dense Metrology

Melanie Ast, S. Steinlechner, Roman Schnabel

Published Oct 27, 2016• 24 citations

Abstract

Quantum-dense metrology constitutes a special case of quantum metrology in which two orthogonal phase space projections of a signal are simultaneously sensed beyond the shot-noise limit. Previously, it was shown that the additional sensing channel that is provided by quantum-dense metrology contains information that can be used to identify and to discard corrupted segments from the measurement data. Here, we propose and demonstrate a new method in which this information is used for improving the sensitivity without discarding any measurement segments. Our measurement reached sub-shot-noise performance, although initially strong classical noise polluted the data. The new method has high potential for improving the noise spectral density of gravitational-wave detectors at signal frequencies of high astrophysical relevance.

DOI: 10.1103/physrevlett.117.180801

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