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Beating the classical precision limit with spin-1 Dicke states of more than 10,000 atoms. | LitMetric

Beating the classical precision limit with spin-1 Dicke states of more than 10,000 atoms.

Proc Natl Acad Sci U S A

State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China;

Published: June 2018

AI Article Synopsis

Article Abstract

Interferometry is a paradigm for most precision measurements. Using N uncorrelated particles, the achievable precision for a two-mode (two-path) interferometer is bounded by the standard quantum limit (SQL), [Formula: see text], due to the discrete (quanta) nature of individual measurements. Despite being a challenging benchmark, the two-mode SQL has been approached in a number of systems, including the Laser Interferometer Gravitational-Wave Observatory and today's best atomic clocks. For multimode interferometry, the SQL becomes [Formula: see text] using modes. Higher precision can also be achieved using entangled particles such that quantum noises from individual particles cancel out. In this work, we demonstrate an interferometric precision of [Formula: see text] dB beyond the three-mode SQL, using balanced spin-1 (three-mode) Dicke states containing thousands of entangled atoms. The input quantum states are deterministically generated by controlled quantum phase transition and exhibit close to ideal quality. Our work shines light on the pursuit of quantum metrology beyond SQL.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6016791PMC
http://dx.doi.org/10.1073/pnas.1715105115DOI Listing

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