Versatile Gaussian probes for squeezing estimation
We consider an instance of “black-box” quantum metrology in the Gaussian framework, where we aim to estimate the amount of squeezing applied on an input probe, without previous knowledge on the phase of the applied squeezing. By taking the quantum Fisher information (QFI) as the figure of merit, we...
| Main Authors: | , , , , , |
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| Format: | Article |
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American Physical Society
2017
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| Online Access: | https://eprints.nottingham.ac.uk/42948/ |
| _version_ | 1848796608424050688 |
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| author | Rigovacca, Luca Farace, Alessandro Souza, Leonardo A. M. De Pasquale, Antonella Giovannetti, Vittorio Adesso, Gerardo |
| author_facet | Rigovacca, Luca Farace, Alessandro Souza, Leonardo A. M. De Pasquale, Antonella Giovannetti, Vittorio Adesso, Gerardo |
| author_sort | Rigovacca, Luca |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | We consider an instance of “black-box” quantum metrology in the Gaussian framework, where we aim to estimate the amount of squeezing applied on an input probe, without previous knowledge on the phase of the applied squeezing. By taking the quantum Fisher information (QFI) as the figure of merit, we evaluate its average and variance with respect to this phase in order to identify probe states that yield good precision for many different squeezing directions. We first consider the case of single-mode Gaussian probes with the same energy, and find that pure squeezed states maximize the average quantum Fisher information (AvQFI) at the cost of a performance that oscillates strongly as the squeezing direction is changed. Although the variance can be brought to zero by correlating the probing system with a reference mode, the maximum AvQFI cannot be increased in the same way. A different scenario opens if one takes into account the effects of photon losses: coherent states represent the optimal single-mode choice when losses exceed a certain threshold and, moreover, correlated probes can now yield larger AvQFI values than all single-mode states, on top of having zero variance. |
| first_indexed | 2025-11-14T19:50:41Z |
| format | Article |
| id | nottingham-42948 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:50:41Z |
| publishDate | 2017 |
| publisher | American Physical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-429482020-05-04T18:45:45Z https://eprints.nottingham.ac.uk/42948/ Versatile Gaussian probes for squeezing estimation Rigovacca, Luca Farace, Alessandro Souza, Leonardo A. M. De Pasquale, Antonella Giovannetti, Vittorio Adesso, Gerardo We consider an instance of “black-box” quantum metrology in the Gaussian framework, where we aim to estimate the amount of squeezing applied on an input probe, without previous knowledge on the phase of the applied squeezing. By taking the quantum Fisher information (QFI) as the figure of merit, we evaluate its average and variance with respect to this phase in order to identify probe states that yield good precision for many different squeezing directions. We first consider the case of single-mode Gaussian probes with the same energy, and find that pure squeezed states maximize the average quantum Fisher information (AvQFI) at the cost of a performance that oscillates strongly as the squeezing direction is changed. Although the variance can be brought to zero by correlating the probing system with a reference mode, the maximum AvQFI cannot be increased in the same way. A different scenario opens if one takes into account the effects of photon losses: coherent states represent the optimal single-mode choice when losses exceed a certain threshold and, moreover, correlated probes can now yield larger AvQFI values than all single-mode states, on top of having zero variance. American Physical Society 2017-05-16 Article PeerReviewed Rigovacca, Luca, Farace, Alessandro, Souza, Leonardo A. M., De Pasquale, Antonella, Giovannetti, Vittorio and Adesso, Gerardo (2017) Versatile Gaussian probes for squeezing estimation. Physical Review A, 95 (5). 052331/1-052331/16. ISSN 2469-9934 https://journals.aps.org/pra/abstract/10.1103/PhysRevA.95.052331 doi:10.1103/PhysRevA.95.052331 doi:10.1103/PhysRevA.95.052331 |
| spellingShingle | Rigovacca, Luca Farace, Alessandro Souza, Leonardo A. M. De Pasquale, Antonella Giovannetti, Vittorio Adesso, Gerardo Versatile Gaussian probes for squeezing estimation |
| title | Versatile Gaussian probes for squeezing estimation |
| title_full | Versatile Gaussian probes for squeezing estimation |
| title_fullStr | Versatile Gaussian probes for squeezing estimation |
| title_full_unstemmed | Versatile Gaussian probes for squeezing estimation |
| title_short | Versatile Gaussian probes for squeezing estimation |
| title_sort | versatile gaussian probes for squeezing estimation |
| url | https://eprints.nottingham.ac.uk/42948/ https://eprints.nottingham.ac.uk/42948/ https://eprints.nottingham.ac.uk/42948/ |