Gaussian interferometric power
The interferometric power of a bipartite quantum state quantifies the precision, measured by quantum Fisher information, that such a state enables for the estimation of a parameter embedded in a unitary dynamics applied to one subsystem only, in the worst-case scenario where a full knowledge of the...
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| Format: | Article |
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American Physical Society
2014
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| Online Access: | https://eprints.nottingham.ac.uk/47212/ |
| _version_ | 1848797491278905344 |
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| author | Adesso, Gerardo |
| author_facet | Adesso, Gerardo |
| author_sort | Adesso, Gerardo |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | The interferometric power of a bipartite quantum state quantifies the precision, measured by quantum Fisher information, that such a state enables for the estimation of a parameter embedded in a unitary dynamics applied to one subsystem only, in the worst-case scenario where a full knowledge of the generator of the dynamics is not available a priori. For finite-dimensional systems, this quantity was proven to be a faithful measure of quantum correlations beyond entanglement. Here we extend the notion of interferometric power to the technologically relevant setting of optical interferometry with continuous-variable probes. By restricting to Gaussian local dynamics, we obtain a closed formula for the interferometric power of all two-mode Gaussian states. We identify separable and entangled Gaussian states which maximize the interferometric power at fixed mean photon number of the probes and discuss the associated metrological scaling. At fixed entanglement of the probes, highly thermalized states can guarantee considerably larger precision than pure two-mode squeezed states. |
| first_indexed | 2025-11-14T20:04:43Z |
| format | Article |
| id | nottingham-47212 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T20:04:43Z |
| publishDate | 2014 |
| publisher | American Physical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-472122020-05-04T16:52:16Z https://eprints.nottingham.ac.uk/47212/ Gaussian interferometric power Adesso, Gerardo The interferometric power of a bipartite quantum state quantifies the precision, measured by quantum Fisher information, that such a state enables for the estimation of a parameter embedded in a unitary dynamics applied to one subsystem only, in the worst-case scenario where a full knowledge of the generator of the dynamics is not available a priori. For finite-dimensional systems, this quantity was proven to be a faithful measure of quantum correlations beyond entanglement. Here we extend the notion of interferometric power to the technologically relevant setting of optical interferometry with continuous-variable probes. By restricting to Gaussian local dynamics, we obtain a closed formula for the interferometric power of all two-mode Gaussian states. We identify separable and entangled Gaussian states which maximize the interferometric power at fixed mean photon number of the probes and discuss the associated metrological scaling. At fixed entanglement of the probes, highly thermalized states can guarantee considerably larger precision than pure two-mode squeezed states. American Physical Society 2014-08-20 Article PeerReviewed Adesso, Gerardo (2014) Gaussian interferometric power. Physical Review A, 90 (2). 022321-1-022321-6. ISSN 2469-9934 https://journals.aps.org/pra/abstract/10.1103/PhysRevA.90.022321 doi:10.1103/PhysRevA.90.022321 doi:10.1103/PhysRevA.90.022321 |
| spellingShingle | Adesso, Gerardo Gaussian interferometric power |
| title | Gaussian interferometric power |
| title_full | Gaussian interferometric power |
| title_fullStr | Gaussian interferometric power |
| title_full_unstemmed | Gaussian interferometric power |
| title_short | Gaussian interferometric power |
| title_sort | gaussian interferometric power |
| url | https://eprints.nottingham.ac.uk/47212/ https://eprints.nottingham.ac.uk/47212/ https://eprints.nottingham.ac.uk/47212/ |