{"title":"Ab Initio 自纡回激子","authors":"Yunfei Bai, Yaxian Wang, Sheng Meng","doi":"10.1103/physrevlett.133.046903","DOIUrl":null,"url":null,"abstract":"We propose a new formalism and an effective computational framework to study self-trapped excitons (STEs) in insulators and semiconductors from first principles. Using the many-body Bethe-Salpeter equation in combination with perturbation theory, we are able to obtain the mode- and momentum-resolved exciton-phonon coupling matrix element in a perturbative scheme and explicitly solve the real space localization of the electron (hole), as well as the lattice distortion. Further, this method allows us to compute the STE potential energy surface and evaluate the STE formation energy and Stokes shift. We demonstrate our approach using two-dimensional magnetic semiconductor chromium trihalides and a wide-gap insulator BeO, the latter of which features dark excitons, and make predictions of their Stokes shift and coherent phonon generation which we hope will spark future experiments such as photoluminescence and transient absorption studies.","PeriodicalId":20069,"journal":{"name":"Physical review letters","volume":null,"pages":null},"PeriodicalIF":8.1000,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Ab Initio Self-Trapped Excitons\",\"authors\":\"Yunfei Bai, Yaxian Wang, Sheng Meng\",\"doi\":\"10.1103/physrevlett.133.046903\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We propose a new formalism and an effective computational framework to study self-trapped excitons (STEs) in insulators and semiconductors from first principles. Using the many-body Bethe-Salpeter equation in combination with perturbation theory, we are able to obtain the mode- and momentum-resolved exciton-phonon coupling matrix element in a perturbative scheme and explicitly solve the real space localization of the electron (hole), as well as the lattice distortion. Further, this method allows us to compute the STE potential energy surface and evaluate the STE formation energy and Stokes shift. We demonstrate our approach using two-dimensional magnetic semiconductor chromium trihalides and a wide-gap insulator BeO, the latter of which features dark excitons, and make predictions of their Stokes shift and coherent phonon generation which we hope will spark future experiments such as photoluminescence and transient absorption studies.\",\"PeriodicalId\":20069,\"journal\":{\"name\":\"Physical review letters\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":8.1000,\"publicationDate\":\"2024-07-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physical review letters\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1103/physrevlett.133.046903\",\"RegionNum\":1,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"PHYSICS, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical review letters","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1103/physrevlett.133.046903","RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
We propose a new formalism and an effective computational framework to study self-trapped excitons (STEs) in insulators and semiconductors from first principles. Using the many-body Bethe-Salpeter equation in combination with perturbation theory, we are able to obtain the mode- and momentum-resolved exciton-phonon coupling matrix element in a perturbative scheme and explicitly solve the real space localization of the electron (hole), as well as the lattice distortion. Further, this method allows us to compute the STE potential energy surface and evaluate the STE formation energy and Stokes shift. We demonstrate our approach using two-dimensional magnetic semiconductor chromium trihalides and a wide-gap insulator BeO, the latter of which features dark excitons, and make predictions of their Stokes shift and coherent phonon generation which we hope will spark future experiments such as photoluminescence and transient absorption studies.
期刊介绍:
Physical review letters(PRL)covers the full range of applied, fundamental, and interdisciplinary physics research topics:
General physics, including statistical and quantum mechanics and quantum information
Gravitation, astrophysics, and cosmology
Elementary particles and fields
Nuclear physics
Atomic, molecular, and optical physics
Nonlinear dynamics, fluid dynamics, and classical optics
Plasma and beam physics
Condensed matter and materials physics
Polymers, soft matter, biological, climate and interdisciplinary physics, including networks