Enhanced Gravitational Entanglement via Modulated Optomechanics

authored by: Douglas A.K. Plato, Dennis Rätzel, Chuanqi Wan
Abstract: The role of entanglement in determining the non-classicality of a given interaction has gained significant traction over the last few years. In particular, as the basis for new experimental proposals to test the quantum nature of the gravitational field. Here we show that the rate of gravity mediated entanglement between two otherwise isolated optomechanical systems can be significantly increased by modulating the optomechanical coupling. This is most pronounced for low mass, high frequency systems – convenient for reaching the quantum regime – and can lead to improvements of several orders of magnitude, as well as a broadening of the measurement window. Nevertheless, significant obstacles still remain. In particular, we find that modulations increase decoherence effects at the same rate as the entanglement improvements. This adds to the growing evidence that the constraint on noise (acting on the position d.o.f) depends only on the particle mass, separation, and temperature of the environment and cannot be improved by novel quantum control. Finally, we highlight the close connection between the observation of quantum correlations and the limits of measurement precision derived via the Cramér-Rao Bound. An immediate consequence is that probing superpositions of the gravitational field places similar demands on detector sensitivity as entanglement verification.
External Organisation(s): University of Rostock
University of Bremen
Humboldt-Universität zu Berlin (HU Berlin)
Type: Article
Journal: Quantum
Volume: 7
ISSN: 2521-327X
Publication date: 08.11.2023
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Atomic and Molecular Physics, and Optics, Physics and Astronomy (miscellaneous)
Electronic version(s): https://doi.org/10.22331/q-2023-11-08-1177 (Access: Open)

BibTeX

@article{50bc6c6dae0e4a838fbf45219ad8efb1,
title = "Enhanced Gravitational Entanglement via Modulated Optomechanics",
abstract = "The role of entanglement in determining the non-classicality of a given interaction has gained significant traction over the last few years. In particular, as the basis for new experimental proposals to test the quantum nature of the gravitational field. Here we show that the rate of gravity mediated entanglement between two otherwise isolated optomechanical systems can be significantly increased by modulating the optomechanical coupling. This is most pronounced for low mass, high frequency systems – convenient for reaching the quantum regime – and can lead to improvements of several orders of magnitude, as well as a broadening of the measurement window. Nevertheless, significant obstacles still remain. In particular, we find that modulations increase decoherence effects at the same rate as the entanglement improvements. This adds to the growing evidence that the constraint on noise (acting on the position d.o.f) depends only on the particle mass, separation, and temperature of the environment and cannot be improved by novel quantum control. Finally, we highlight the close connection between the observation of quantum correlations and the limits of measurement precision derived via the Cram{\'e}r-Rao Bound. An immediate consequence is that probing superpositions of the gravitational field places similar demands on detector sensitivity as entanglement verification.",
author = "Plato, {Douglas A.K.} and Dennis R{\"a}tzel and Chuanqi Wan",
note = "Funding Information: The authors would like to thank Sofia Qvarfort and Stefan Scheel for helpful remarks and discussions. A. D. K. P. was partially supported by the European Social Fund (ESF) and the Ministry of Education, Science and Culture of Mecklenburg-Western Pomerania (Germany) within the project NEISS under grant no ESF/14-BM-A55-0006/19. D.R. acknowledges funding by the Federal Ministry of Education and Research of Germany in the project “Open6GHub” (grant number: 16KISK016) and support through the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany{\textquoteright}s Excellence Strategy – EXC-2123 QuantumFrontiers – 390837967, the Research Training Group 1620 “Models of Gravity” and the TerraQ initiative from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project-ID 434617780 – SFB 1464.",
year = "2023",
month = nov,
day = "8",
doi = "10.22331/q-2023-11-08-1177",
language = "English",
volume = "7",
journal = "Quantum",
issn = "2521-327X",
publisher = "Verein zur Forderung des Open Access Publizierens in den Quantenwissenschaften",
}