The effect of thermal photons on exceptional points in coupled resonators
Abstract We analyse two quantum systems with hidden parity-time ( $${\mathscr {P}\mathscr {T}}$$ P T ) symmetry: one is an optical device, whereas another is a superconducting microwave-frequency device. To investigate their symmetry, we introduce a damping frame (DF), in which loss and gain terms f...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2023-04-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-023-32864-2 |
| _version_ | 1797452937764536320 |
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| author | Grzegorz Chimczak Anna Kowalewska-Kudłaszyk Ewelina Lange Karol Bartkiewicz Jan Peřina |
| author_facet | Grzegorz Chimczak Anna Kowalewska-Kudłaszyk Ewelina Lange Karol Bartkiewicz Jan Peřina |
| author_sort | Grzegorz Chimczak |
| collection | DOAJ |
| description | Abstract We analyse two quantum systems with hidden parity-time ( $${\mathscr {P}\mathscr {T}}$$ P T ) symmetry: one is an optical device, whereas another is a superconducting microwave-frequency device. To investigate their symmetry, we introduce a damping frame (DF), in which loss and gain terms for a given Hamiltonian are balanced. We show that the non-Hermitian Hamiltonians of both systems can be tuned to reach an exceptional point (EP), i.e., the point in parameter space at which a transition from broken to unbroken hidden $${\mathscr {P}\mathscr {T}}$$ P T symmetry takes place. We calculate a degeneracy of a Liouvillian superoperator, which is called the Liouvillian exceptional point (LEP), and show that, in the optical domain, LEP is equivalent to EP obtained from the non-Hermitian Hamiltonian (HEP). We also report breaking the equivalence between LEP and HEP by a non-zero number of thermal photons for the microwave-frequency system. |
| first_indexed | 2024-03-09T15:15:54Z |
| format | Article |
| id | doaj.art-bc3ed9fe3e424f8fa7c2afbfc647d571 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-03-09T15:15:54Z |
| publishDate | 2023-04-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-bc3ed9fe3e424f8fa7c2afbfc647d5712023-11-26T13:05:27ZengNature PortfolioScientific Reports2045-23222023-04-0113111110.1038/s41598-023-32864-2The effect of thermal photons on exceptional points in coupled resonatorsGrzegorz Chimczak0Anna Kowalewska-Kudłaszyk1Ewelina Lange2Karol Bartkiewicz3Jan Peřina4Institute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz UniversityInstitute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz UniversityInstitute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz UniversityInstitute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz UniversityRCPTM, Joint Laboratory of Optics of Palacký University and Institute of Physics of Czech Academy of SciencesAbstract We analyse two quantum systems with hidden parity-time ( $${\mathscr {P}\mathscr {T}}$$ P T ) symmetry: one is an optical device, whereas another is a superconducting microwave-frequency device. To investigate their symmetry, we introduce a damping frame (DF), in which loss and gain terms for a given Hamiltonian are balanced. We show that the non-Hermitian Hamiltonians of both systems can be tuned to reach an exceptional point (EP), i.e., the point in parameter space at which a transition from broken to unbroken hidden $${\mathscr {P}\mathscr {T}}$$ P T symmetry takes place. We calculate a degeneracy of a Liouvillian superoperator, which is called the Liouvillian exceptional point (LEP), and show that, in the optical domain, LEP is equivalent to EP obtained from the non-Hermitian Hamiltonian (HEP). We also report breaking the equivalence between LEP and HEP by a non-zero number of thermal photons for the microwave-frequency system.https://doi.org/10.1038/s41598-023-32864-2 |
| spellingShingle | Grzegorz Chimczak Anna Kowalewska-Kudłaszyk Ewelina Lange Karol Bartkiewicz Jan Peřina The effect of thermal photons on exceptional points in coupled resonators Scientific Reports |
| title | The effect of thermal photons on exceptional points in coupled resonators |
| title_full | The effect of thermal photons on exceptional points in coupled resonators |
| title_fullStr | The effect of thermal photons on exceptional points in coupled resonators |
| title_full_unstemmed | The effect of thermal photons on exceptional points in coupled resonators |
| title_short | The effect of thermal photons on exceptional points in coupled resonators |
| title_sort | effect of thermal photons on exceptional points in coupled resonators |
| url | https://doi.org/10.1038/s41598-023-32864-2 |
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