Imaginarity-free quantum multiparameter estimation
Multiparameter quantum estimation is made difficult by the following three obstacles. First, incompatibility among different physical quantities poses a limit on the attainable precision. Second, the ultimate precision is not saturated until you discover the optimal measurement. Third, the optimal m...
Main Authors: | , |
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Format: | Article |
Language: | English |
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Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften
2022-03-01
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Series: | Quantum |
Online Access: | https://quantum-journal.org/papers/q-2022-03-10-665/pdf/ |
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author | Jisho Miyazaki Keiji Matsumoto |
author_facet | Jisho Miyazaki Keiji Matsumoto |
author_sort | Jisho Miyazaki |
collection | DOAJ |
description | Multiparameter quantum estimation is made difficult by the following three obstacles. First, incompatibility among different physical quantities poses a limit on the attainable precision. Second, the ultimate precision is not saturated until you discover the optimal measurement. Third, the optimal measurement may generally depend on the target values of parameters, and thus may be impossible to perform for unknown target states.
We present a method to circumvent these three obstacles. A class of quantum statistical models, which utilizes antiunitary symmetries or, equivalently, real density matrices, offers compatible multiparameter estimations. The symmetries accompany the target-independent optimal measurements for pure-state models. Based on this finding, we propose methods to implement antiunitary symmetries for quantum metrology schemes. We further introduce a function which measures antiunitary asymmetry of quantum statistical models as a potential tool to characterize quantumness of phase transitions. |
first_indexed | 2024-12-13T09:19:59Z |
format | Article |
id | doaj.art-983235b020f046dcb97ea21492226edb |
institution | Directory Open Access Journal |
issn | 2521-327X |
language | English |
last_indexed | 2024-12-13T09:19:59Z |
publishDate | 2022-03-01 |
publisher | Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften |
record_format | Article |
series | Quantum |
spelling | doaj.art-983235b020f046dcb97ea21492226edb2022-12-21T23:52:45ZengVerein zur Förderung des Open Access Publizierens in den QuantenwissenschaftenQuantum2521-327X2022-03-01666510.22331/q-2022-03-10-66510.22331/q-2022-03-10-665Imaginarity-free quantum multiparameter estimationJisho MiyazakiKeiji MatsumotoMultiparameter quantum estimation is made difficult by the following three obstacles. First, incompatibility among different physical quantities poses a limit on the attainable precision. Second, the ultimate precision is not saturated until you discover the optimal measurement. Third, the optimal measurement may generally depend on the target values of parameters, and thus may be impossible to perform for unknown target states. We present a method to circumvent these three obstacles. A class of quantum statistical models, which utilizes antiunitary symmetries or, equivalently, real density matrices, offers compatible multiparameter estimations. The symmetries accompany the target-independent optimal measurements for pure-state models. Based on this finding, we propose methods to implement antiunitary symmetries for quantum metrology schemes. We further introduce a function which measures antiunitary asymmetry of quantum statistical models as a potential tool to characterize quantumness of phase transitions.https://quantum-journal.org/papers/q-2022-03-10-665/pdf/ |
spellingShingle | Jisho Miyazaki Keiji Matsumoto Imaginarity-free quantum multiparameter estimation Quantum |
title | Imaginarity-free quantum multiparameter estimation |
title_full | Imaginarity-free quantum multiparameter estimation |
title_fullStr | Imaginarity-free quantum multiparameter estimation |
title_full_unstemmed | Imaginarity-free quantum multiparameter estimation |
title_short | Imaginarity-free quantum multiparameter estimation |
title_sort | imaginarity free quantum multiparameter estimation |
url | https://quantum-journal.org/papers/q-2022-03-10-665/pdf/ |
work_keys_str_mv | AT jishomiyazaki imaginarityfreequantummultiparameterestimation AT keijimatsumoto imaginarityfreequantummultiparameterestimation |