{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T01:28:27Z","timestamp":1775784507267,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T00:00:00Z","timestamp":1631145600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["12071336; 11671006"],"award-info":[{"award-number":["12071336; 11671006"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Generally speaking, it is difficult to compute the values of the Gaussian quantum discord and Gaussian geometric discord for Gaussian states, which limits their application. In the present paper, for any (n+m)-mode continuous-variable system, a computable Gaussian quantum correlation M is proposed. For any state \u03c1AB of the system, M(\u03c1AB) depends only on the covariant matrix of \u03c1AB without any measurements performed on a subsystem or any optimization procedures, and thus is easily computed. Furthermore, M has the following attractive properties: (1) M is independent of the mean of states, is symmetric about the subsystems and has no ancilla problem; (2) M is locally Gaussian unitary invariant; (3) for a Gaussian state \u03c1AB, M(\u03c1AB)=0 if and only if \u03c1AB is a product state; and (4) 0\u2264M((\u03a6A\u2297\u03a6B)\u03c1AB)\u2264M(\u03c1AB) holds for any Gaussian state \u03c1AB and any Gaussian channels \u03a6A and \u03a6B performed on the subsystem A and B, respectively. Therefore, M is a nice Gaussian correlation which describes the same Gaussian correlation as Gaussian quantum discord and Gaussian geometric discord when restricted on Gaussian states. As an application of M, a noninvasive quantum method for detecting intracellular temperature is proposed.<\/jats:p>","DOI":"10.3390\/e23091190","type":"journal-article","created":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T12:20:37Z","timestamp":1631190037000},"page":"1190","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["A Computable Gaussian Quantum Correlation for Continuous-Variable Systems"],"prefix":"10.3390","volume":"23","author":[{"given":"Liang","family":"Liu","sequence":"first","affiliation":[{"name":"College of Mathematics, Taiyuan University of Technology, Taiyuan 030024, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6534-9228","authenticated-orcid":false,"given":"Jinchuan","family":"Hou","sequence":"additional","affiliation":[{"name":"College of Mathematics, Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Xiaofei","family":"Qi","sequence":"additional","affiliation":[{"name":"School of Mathematical Science, Shanxi University, Taiyuan 030006, China"},{"name":"Institute of Big Data Science and Industry, Shanxi University, Taiyuan 030006, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"865","DOI":"10.1103\/RevModPhys.81.865","article-title":"Quantum entanglement","volume":"81","author":"Horodecki","year":"2009","journal-title":"Rev. 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