Variational quantum algorithm for estimating the quantum Fisher information
The quantum Fisher information (QFI) quantifies the ultimate precision of estimating a parameter from a quantum state and can be regarded as a reliability measure of a quantum system as a quantum sensor. However, estimation of the QFI for a mixed state is in general a computationally demanding task....
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2022-02-01
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| Series: | Physical Review Research |
| Online Access: | http://doi.org/10.1103/PhysRevResearch.4.013083 |
| _version_ | 1797210857499787264 |
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| author | Jacob L. Beckey M. Cerezo Akira Sone Patrick J. Coles |
| author_facet | Jacob L. Beckey M. Cerezo Akira Sone Patrick J. Coles |
| author_sort | Jacob L. Beckey |
| collection | DOAJ |
| description | The quantum Fisher information (QFI) quantifies the ultimate precision of estimating a parameter from a quantum state and can be regarded as a reliability measure of a quantum system as a quantum sensor. However, estimation of the QFI for a mixed state is in general a computationally demanding task. In this paper we present a variational quantum algorithm called variational quantum Fisher information estimation (VQFIE) to address this task. By estimating lower and upper bounds on the QFI, based on bounding the fidelity, VQFIE outputs a range in which the actual QFI lies. This result can then be used to variationally prepare the state that maximizes the QFI, for the application of quantum sensing. In contrast to previous approaches, VQFIE does not require knowledge of the explicit form of the sensor dynamics. We simulate the algorithm for a magnetometry setup and demonstrate the tightening of our bounds as the state purity increases. For this example, we compare our bounds with literature bounds and show that our bounds are tighter. |
| first_indexed | 2024-04-24T10:17:15Z |
| format | Article |
| id | doaj.art-5f8701fe68b94cb0b1cac2c68a8b2ad6 |
| institution | Directory Open Access Journal |
| issn | 2643-1564 |
| language | English |
| last_indexed | 2024-04-24T10:17:15Z |
| publishDate | 2022-02-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review Research |
| spelling | doaj.art-5f8701fe68b94cb0b1cac2c68a8b2ad62024-04-12T17:17:41ZengAmerican Physical SocietyPhysical Review Research2643-15642022-02-014101308310.1103/PhysRevResearch.4.013083Variational quantum algorithm for estimating the quantum Fisher informationJacob L. BeckeyM. CerezoAkira SonePatrick J. ColesThe quantum Fisher information (QFI) quantifies the ultimate precision of estimating a parameter from a quantum state and can be regarded as a reliability measure of a quantum system as a quantum sensor. However, estimation of the QFI for a mixed state is in general a computationally demanding task. In this paper we present a variational quantum algorithm called variational quantum Fisher information estimation (VQFIE) to address this task. By estimating lower and upper bounds on the QFI, based on bounding the fidelity, VQFIE outputs a range in which the actual QFI lies. This result can then be used to variationally prepare the state that maximizes the QFI, for the application of quantum sensing. In contrast to previous approaches, VQFIE does not require knowledge of the explicit form of the sensor dynamics. We simulate the algorithm for a magnetometry setup and demonstrate the tightening of our bounds as the state purity increases. For this example, we compare our bounds with literature bounds and show that our bounds are tighter.http://doi.org/10.1103/PhysRevResearch.4.013083 |
| spellingShingle | Jacob L. Beckey M. Cerezo Akira Sone Patrick J. Coles Variational quantum algorithm for estimating the quantum Fisher information Physical Review Research |
| title | Variational quantum algorithm for estimating the quantum Fisher information |
| title_full | Variational quantum algorithm for estimating the quantum Fisher information |
| title_fullStr | Variational quantum algorithm for estimating the quantum Fisher information |
| title_full_unstemmed | Variational quantum algorithm for estimating the quantum Fisher information |
| title_short | Variational quantum algorithm for estimating the quantum Fisher information |
| title_sort | variational quantum algorithm for estimating the quantum fisher information |
| url | http://doi.org/10.1103/PhysRevResearch.4.013083 |
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