Magnetotactic bacterial populations studied with a Pound-Drever-Hall atomic magnetometer

Magnetotactic bacterial populations studied with a Pound-Drever-Hall atomic magnetometer | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Magnetotactic bacterial populations studied with a Pound-Drever-Hall atomic magnetometer Maria Hernandez Ruiz, Christopher Kiehl, Vito Giovanni Lucivero, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7828719/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Mar, 2026 Read the published version in EPJ Quantum Technology → Version 1 posted 9 You are reading this latest preprint version Abstract We demonstrate an optically pumped magnetometer that monitors spin polarization using Pound Drever Hall (PDH) technique. The instrument exhibits a noise floor of \SI{22.2}{\pico\tesla\per\sqrt\hertz} limited by optical photon shot noise, short-term instability of \(((\SI{30.8}{\pico\tesla\per\sqrt\hertz} )/\sqrt{\tauAllan})\) for averaging times \((\tauAllan \le \SI{0.2}{\second})\) , instability below \SI{70}{\pico\tesla} for \((\SI{0.2}{\second} \le \tauAllan \le \SI{20}{\second})\) and a minimum instability of \SI{47}{\pico\tesla} at \((\tauAllan = \SI{6}{\second})\) . We apply the OPM to investigate the ability of magnetotactic bacteria (Magnetospirillum gryphiswaldense, MSR-1) to orient in externally applied magnetic fields. Observing an opaque, concentrated suspension, we detect deviations from exponential relaxation dynamics on second time-scales, which give information about the dispersion of bacterial magnetic moment and rotational damping coefficient. These parameters are observed to evolve as the population further concentrates due to evaporation and settling. To our knowledge, this is the first time such magnetic inhomogeneities and long-term relaxation deviations have been directly observed.This study showcases both the sensitivity and stability of our OPM and its potential for probing biophysical processes. atomic magnetometer magnetotactic bacteria cavity-enhancement quantum sensing Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 10 Mar, 2026 Read the published version in EPJ Quantum Technology → Version 1 posted Editorial decision: Revision requested 04 Jan, 2026 Reviews received at journal 02 Jan, 2026 Reviewers agreed at journal 15 Dec, 2025 Reviews received at journal 12 Nov, 2025 Reviewers agreed at journal 21 Oct, 2025 Reviewers invited by journal 16 Oct, 2025 Editor assigned by journal 14 Oct, 2025 Submission checks completed at journal 14 Oct, 2025 First submitted to journal 10 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7828719","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":535864248,"identity":"57422193-76f0-4221-b04b-4123afa739df","order_by":0,"name":"Maria Hernandez Ruiz","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/klEQVRIiWNgGAWjYBACgwMMDEB0GMLjYWCQY2NgfIBXiyW6FmM2BmYDvFrsD4AphJbEBkJazI6ffXjgB8NhOfPZzc8evKmoS+9jPwx0WcVh3FrOpBsc7GH4byxz55i54ZwzbLltPMlAa87g0XIgjeEAD8PhxBkSCWbSvG08uW0S/MckGNtwazE4/4zh4B+Gw/UzJNK/SfP+k0hnk2Bmk2D8h0fLjTSGw0BbEiQkcoC2NBgkQLQ04NPyjOGwjMFhwxkSOWWSc44lGIL9knAsHY/D0pg/vqk4LC8hkb5N4k1Nnbx8OzDEPtRY49QC1YgukEBAwygYBaNgFIwC/AAAHptTJ0qTCFIAAAAASUVORK5CYII=","orcid":"","institution":"Institute of Photonic Sciences","correspondingAuthor":true,"prefix":"","firstName":"Maria","middleName":"Hernandez","lastName":"Ruiz","suffix":""},{"id":535864251,"identity":"e009fbf2-eb9c-423a-8b66-b3073adc9626","order_by":1,"name":"Christopher Kiehl","email":"","orcid":"","institution":"Institute of Photonic Sciences","correspondingAuthor":false,"prefix":"","firstName":"Christopher","middleName":"","lastName":"Kiehl","suffix":""},{"id":535864254,"identity":"d5e32d63-5671-4d10-bd37-54897cc098b1","order_by":2,"name":"Vito Giovanni Lucivero","email":"","orcid":"","institution":"Institute of Photonic Sciences","correspondingAuthor":false,"prefix":"","firstName":"Vito","middleName":"Giovanni","lastName":"Lucivero","suffix":""},{"id":535864255,"identity":"199b1d3e-a811-4b5f-9c1e-35cb4a2ddebb","order_by":3,"name":"Morgan W. 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Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"atomic magnetometer, magnetotactic bacteria, cavity-enhancement, quantum sensing","lastPublishedDoi":"10.21203/rs.3.rs-7828719/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7828719/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eWe demonstrate an optically pumped magnetometer that monitors spin polarization using Pound Drever Hall (PDH) technique. The instrument exhibits a noise floor of \\SI{22.2}{\\pico\\tesla\\per\\sqrt\\hertz} limited by optical photon shot noise, short-term instability of \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(((\\SI{30.8}{\\pico\\tesla\\per\\sqrt\\hertz} )/\\sqrt{\\tauAllan})\\)\u003c/span\u003e\u003c/span\u003e for averaging times \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\((\\tauAllan \\le \\SI{0.2}{\\second})\\)\u003c/span\u003e\u003c/span\u003e, instability below \\SI{70}{\\pico\\tesla} for \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\((\\SI{0.2}{\\second} \\le \\tauAllan \\le \\SI{20}{\\second})\\)\u003c/span\u003e\u003c/span\u003e and a minimum instability of \\SI{47}{\\pico\\tesla} at \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\((\\tauAllan = \\SI{6}{\\second})\\)\u003c/span\u003e\u003c/span\u003e. We apply the OPM to investigate the ability of magnetotactic bacteria (Magnetospirillum gryphiswaldense, MSR-1) to orient in externally applied magnetic fields. Observing an opaque, concentrated suspension, we detect deviations from exponential relaxation dynamics on second time-scales, which give information about the dispersion of bacterial magnetic moment and rotational damping coefficient. These parameters are observed to evolve as the population further concentrates due to evaporation and settling. To our knowledge, this is the first time such magnetic inhomogeneities and long-term relaxation deviations have been directly observed.This study showcases both the sensitivity and stability of our OPM and its potential for probing biophysical processes. \u003c/p\u003e","manuscriptTitle":"Magnetotactic bacterial populations studied with a Pound-Drever-Hall atomic magnetometer","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-30 04:54:33","doi":"10.21203/rs.3.rs-7828719/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-04T10:29:59+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-02T22:53:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"187306639059412175983894885383282929636","date":"2025-12-15T17:01:40+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-12T15:56:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"267830178244210012839549981130478075883","date":"2025-10-21T08:13:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-16T06:39:42+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-14T11:42:22+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-14T11:41:33+00:00","index":"","fulltext":""},{"type":"submitted","content":"EPJ Quantum Technology","date":"2025-10-10T15:40:46+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"epj-quantum-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"epjq","sideBox":"Learn more about [EPJ Quantum Technology](http://epjquantumtechnology.springeropen.com)","snPcode":"40507","submissionUrl":"https://submission.nature.com/new-submission/40507/3","title":"EPJ Quantum Technology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6775e630-2de3-494a-94a9-ec0643f67ea1","owner":[],"postedDate":"October 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-03-16T16:08:56+00:00","versionOfRecord":{"articleIdentity":"rs-7828719","link":"https://doi.org/10.1140/epjqt/s40507-026-00487-x","journal":{"identity":"epj-quantum-technology","isVorOnly":false,"title":"EPJ Quantum Technology"},"publishedOn":"2026-03-10 16:00:19","publishedOnDateReadable":"March 10th, 2026"},"versionCreatedAt":"2025-10-30 04:54:33","video":"","vorDoi":"10.1140/epjqt/s40507-026-00487-x","vorDoiUrl":"https://doi.org/10.1140/epjqt/s40507-026-00487-x","workflowStages":[]},"version":"v1","identity":"rs-7828719","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7828719","identity":"rs-7828719","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}