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Entanglement of macroscopic test masses and the Standard Quantum Limit in laser interferometry

Helge Mueller-Ebhardt·Henning Rehbein·Roman Schnabel·Karsten Danzmann·Yanbei Chen
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Abstract

We show that the generation of entanglement of two heavily macroscopic mirrors with masses of up to several kilograms are feasible with state of the art techniques of high-precision laser interferometry. The basis of such a demonstration would be a Michelson interferometer with suspended mirrors and simultaneous homodyne detections at both interferometer output ports. We present the connection between the generation of entanglement and the Standard Quantum Limit (SQL) for a free mass. The SQL is a well-known reference limit in operating interferometers for gravitational-wave detection and provides a measure of when macroscopic entanglement can be observed in the presence of realistic decoherence processes.

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Helge Mueller-Ebhardt, Henning Rehbein, Roman Schnabel, Karsten Danzmann, Yanbei Chen. 2007-11-08. Entanglement of macroscopic test masses and the Standard Quantum Limit in laser interferometry. https://doi.org/10.1103/physrevlett.100.013601

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