Defect induced site-selective self-trapped holes and their optical fingerprints in β-Ga2O3.

Defect induced site-selective self-trapped holes and their optical fingerprints in β-Ga2O3. | 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 Article Defect induced site-selective self-trapped holes and their optical fingerprints in β-Ga 2 O 3 . F. Bermúdez-Mendoza, E. Nogales, B. Méndez, F. Domínguez-Adame, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9008105/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract The monoclinic β-Ga2O3 exhibits strongly linearly polarized ultraviolet luminescence, associated to native defects; however, the microscopic relationship between the tetrahedral (VGaI) and octahedral (VGaII) native gallium vacancies and the observed optical dichroism remains unresolved. By considering spin-polarized hybrid density-functional theory, we demonstrate that both gallium vacancies act as efficient traps for oxygen-centered self-trapped holes (STHs). Specifically, VGaI and VGaII favor different STH configurations localized on inequivalent neighboring oxygen sites, that lead to spin-polarized weakly dispersive defect states closed to the valence-band maximum. These energy levels allow for defect-specific optical transitions to the conduction-band. Thus, the anisotropic real-space STH wavefunctions, dictated by the local Ga-O connectivity, induces a pronounced vacancy-dependent linear dichroism in the near-edge optical response. In this work we establish a correlation between the polarization-resolved optical spectra and the particular spatial distribution of STH generated in presence of the two possible gallium-vacancies in β-Ga2O3 to provide a unified microscopic interpretation of its UV defect luminescence. Physical sciences/Materials science Physical sciences/Optics and photonics Physical sciences/Physics Full Text Additional Declarations No competing interests reported. Supplementary Files SpinGaOsup.pdf Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 15 May, 2026 Reviews received at journal 13 May, 2026 Reviewers agreed at journal 12 May, 2026 Reviews received at journal 01 May, 2026 Reviewers agreed at journal 28 Apr, 2026 Reviewers agreed at journal 18 Apr, 2026 Reviewers invited by journal 18 Apr, 2026 Editor assigned by journal 07 Mar, 2026 Submission checks completed at journal 07 Mar, 2026 First submitted to journal 02 Mar, 2026 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-9008105","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":626332015,"identity":"c6a66a86-da15-4352-a805-67f08d12c521","order_by":0,"name":"F. 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By considering spin-polarized hybrid density-functional theory, we demonstrate that both gallium\nvacancies act as efficient traps for oxygen-centered self-trapped holes (STHs). Specifically, VGaI and VGaII favor different STH configurations localized on inequivalent neighboring oxygen sites, that lead to spin-polarized weakly dispersive defect states closed to the valence-band maximum. These energy levels allow for defect-specific optical transitions to the conduction-band. Thus, the\nanisotropic real-space STH wavefunctions, dictated by the local Ga-O connectivity, induces a pronounced vacancy-dependent linear dichroism in the near-edge optical response. In this work we establish a correlation between the polarization-resolved optical spectra and the particular spatial distribution of STH generated in presence of the two possible gallium-vacancies in β-Ga2O3 to provide a unified microscopic interpretation of its UV defect luminescence.","manuscriptTitle":"Defect induced site-selective self-trapped holes and their optical fingerprints in β-Ga2O3.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-27 07:57:36","doi":"10.21203/rs.3.rs-9008105/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"174268829054752995334273901357175295775","date":"2026-05-15T06:14:14+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-13T13:50:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"166649673895248403048160608740098110324","date":"2026-05-13T03:17:04+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-02T03:37:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"311227853034991513104807984075189378447","date":"2026-04-28T07:39:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"317714537146154726777429956022217706729","date":"2026-04-19T03:17:33+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-19T02:54:03+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-07T18:36:26+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-07T06:31:44+00:00","index":"","fulltext":""},{"type":"submitted","content":"npj Computational Materials","date":"2026-03-02T09:01:25+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"npj-computational-materials","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"npjcompumats","sideBox":"Learn more about [npj Computational Materials](http://www.nature.com/npjcompumats/)","snPcode":"41524","submissionUrl":"https://mts-npjcompumats.nature.com/","title":"npj Computational Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"NPJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"af01069d-7382-4454-88d1-d9d325e66c5e","owner":[],"postedDate":"April 27th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"174268829054752995334273901357175295775","date":"2026-05-15T06:14:14+00:00","index":31,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-13T13:50:26+00:00","index":30,"fulltext":""},{"type":"reviewerAgreed","content":"166649673895248403048160608740098110324","date":"2026-05-13T03:17:04+00:00","index":29,"fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-02T03:37:51+00:00","index":26,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":67060109,"name":"Physical sciences/Materials science"},{"id":67060110,"name":"Physical sciences/Optics and photonics"},{"id":67060111,"name":"Physical sciences/Physics"}],"tags":[],"updatedAt":"2026-04-27T07:57:36+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-27 07:57:36","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9008105","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9008105","identity":"rs-9008105","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}