Exceptional classifications of non-Hermitian systems
Abstract Eigenstate coalescence in non-Hermitian systems is widely observed in diverse scientific domains encompassing optics and open quantum systems. Recent investigations have revealed that adiabatic encircling of exceptional points (EPs) leads to a nontrivial Berry phase in addition to an exchan...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2024-03-01
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| Series: | Communications Physics |
| Online Access: | https://doi.org/10.1038/s42005-024-01595-9 |
| _version_ | 1797233564622782464 |
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| author | Jung-Wan Ryu Jae-Ho Han Chang-Hwan Yi Moon Jip Park Hee Chul Park |
| author_facet | Jung-Wan Ryu Jae-Ho Han Chang-Hwan Yi Moon Jip Park Hee Chul Park |
| author_sort | Jung-Wan Ryu |
| collection | DOAJ |
| description | Abstract Eigenstate coalescence in non-Hermitian systems is widely observed in diverse scientific domains encompassing optics and open quantum systems. Recent investigations have revealed that adiabatic encircling of exceptional points (EPs) leads to a nontrivial Berry phase in addition to an exchange of eigenstates. Based on these phenomena, we propose in this work an exhaustive classification framework for EPs in non-Hermitian physical systems. In contrast to previous classifications that only incorporate the eigenstate exchange effect, our proposed classification gives rise to finer $${{\mathbb{Z}}}_{2}$$ Z 2 classifications depending on the presence of a π Berry phase after the encircling of the EPs. Moreover, by mapping arbitrary one-dimensional systems to the adiabatic encircling of EPs, we can classify one-dimensional non-Hermitian systems characterized by topological phase transitions involving EPs. Applying our exceptional classification to various multiband systems, we expect to enhance the understanding of topological phases in non-Hermitian systems. |
| first_indexed | 2024-04-24T16:18:11Z |
| format | Article |
| id | doaj.art-eca2a7d10bdf49dda566481cb9045cf0 |
| institution | Directory Open Access Journal |
| issn | 2399-3650 |
| language | English |
| last_indexed | 2024-04-24T16:18:11Z |
| publishDate | 2024-03-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Communications Physics |
| spelling | doaj.art-eca2a7d10bdf49dda566481cb9045cf02024-03-31T11:22:52ZengNature PortfolioCommunications Physics2399-36502024-03-01711710.1038/s42005-024-01595-9Exceptional classifications of non-Hermitian systemsJung-Wan Ryu0Jae-Ho Han1Chang-Hwan Yi2Moon Jip Park3Hee Chul Park4Center for Theoretical Physics of Complex Systems, Institute for Basic Science (IBS)Center for Theoretical Physics of Complex Systems, Institute for Basic Science (IBS)Center for Theoretical Physics of Complex Systems, Institute for Basic Science (IBS)Department of Physics, Hanyang UniversityDepartment of Physics, Pukyong National UniversityAbstract Eigenstate coalescence in non-Hermitian systems is widely observed in diverse scientific domains encompassing optics and open quantum systems. Recent investigations have revealed that adiabatic encircling of exceptional points (EPs) leads to a nontrivial Berry phase in addition to an exchange of eigenstates. Based on these phenomena, we propose in this work an exhaustive classification framework for EPs in non-Hermitian physical systems. In contrast to previous classifications that only incorporate the eigenstate exchange effect, our proposed classification gives rise to finer $${{\mathbb{Z}}}_{2}$$ Z 2 classifications depending on the presence of a π Berry phase after the encircling of the EPs. Moreover, by mapping arbitrary one-dimensional systems to the adiabatic encircling of EPs, we can classify one-dimensional non-Hermitian systems characterized by topological phase transitions involving EPs. Applying our exceptional classification to various multiband systems, we expect to enhance the understanding of topological phases in non-Hermitian systems.https://doi.org/10.1038/s42005-024-01595-9 |
| spellingShingle | Jung-Wan Ryu Jae-Ho Han Chang-Hwan Yi Moon Jip Park Hee Chul Park Exceptional classifications of non-Hermitian systems Communications Physics |
| title | Exceptional classifications of non-Hermitian systems |
| title_full | Exceptional classifications of non-Hermitian systems |
| title_fullStr | Exceptional classifications of non-Hermitian systems |
| title_full_unstemmed | Exceptional classifications of non-Hermitian systems |
| title_short | Exceptional classifications of non-Hermitian systems |
| title_sort | exceptional classifications of non hermitian systems |
| url | https://doi.org/10.1038/s42005-024-01595-9 |
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