Recovering parity-time symmetry in highly dispersive coupled optical waveguides
Coupled photonic systems satisfying parity-time symmetry (PTS) provide flexibility to engineer the flow of light including non-reciprocal propagation, perfect laser-absorbers, and ultra-fast switching. Achieving the required index profile for an optical system with ideal PTS, i.e. $n(x)=n{(-x)}^{* }...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2016-01-01
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| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/18/12/125012 |
| _version_ | 1827873617127407616 |
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| author | Ngoc B Nguyen Stefan A Maier Minghui Hong Rupert F Oulton |
| author_facet | Ngoc B Nguyen Stefan A Maier Minghui Hong Rupert F Oulton |
| author_sort | Ngoc B Nguyen |
| collection | DOAJ |
| description | Coupled photonic systems satisfying parity-time symmetry (PTS) provide flexibility to engineer the flow of light including non-reciprocal propagation, perfect laser-absorbers, and ultra-fast switching. Achieving the required index profile for an optical system with ideal PTS, i.e. $n(x)=n{(-x)}^{* }$ , has proven to be difficult due to the challenge of controlling gain, loss and material dispersion simultaneously. Consequently, most research has focused on dilute or low gain optical systems where material dispersion is minimal. In this paper, we study a model system of coupled inorganic semiconductor waveguides with potentially high gain (>1500 cm ^−1 ) and dispersion. Our analysis makes use of coupled mode theory’s parameters to quantify smooth transitions between PTS phases under imperfect conditions. We find that the detrimental influence of gain-induced dispersion is counteracted and the key features of PTS optical systems are recovered by working with non-identical waveguides and bias pumping of the optical waveguides. Our coupled mode theory results show excellent agreement with numerical solutions, proving the robustness of coupled mode theory in describing various degrees of imperfection in systems with PTS. |
| first_indexed | 2024-03-12T16:39:38Z |
| format | Article |
| id | doaj.art-93e41aa72b7840328a8ccd8273d21e2d |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:39:38Z |
| publishDate | 2016-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-93e41aa72b7840328a8ccd8273d21e2d2023-08-08T14:35:40ZengIOP PublishingNew Journal of Physics1367-26302016-01-01181212501210.1088/1367-2630/18/12/125012Recovering parity-time symmetry in highly dispersive coupled optical waveguidesNgoc B Nguyen0Stefan A Maier1Minghui Hong2Rupert F Oulton3Department of Physics, The Blackett Laboratory, Imperial College London, SW7 2AZ, UK; Department of Electrical Computer Engineering, National University of Singapore , 117576, SingaporeDepartment of Physics, The Blackett Laboratory, Imperial College London, SW7 2AZ, UKDepartment of Electrical Computer Engineering, National University of Singapore , 117576, SingaporeDepartment of Physics, The Blackett Laboratory, Imperial College London, SW7 2AZ, UKCoupled photonic systems satisfying parity-time symmetry (PTS) provide flexibility to engineer the flow of light including non-reciprocal propagation, perfect laser-absorbers, and ultra-fast switching. Achieving the required index profile for an optical system with ideal PTS, i.e. $n(x)=n{(-x)}^{* }$ , has proven to be difficult due to the challenge of controlling gain, loss and material dispersion simultaneously. Consequently, most research has focused on dilute or low gain optical systems where material dispersion is minimal. In this paper, we study a model system of coupled inorganic semiconductor waveguides with potentially high gain (>1500 cm ^−1 ) and dispersion. Our analysis makes use of coupled mode theory’s parameters to quantify smooth transitions between PTS phases under imperfect conditions. We find that the detrimental influence of gain-induced dispersion is counteracted and the key features of PTS optical systems are recovered by working with non-identical waveguides and bias pumping of the optical waveguides. Our coupled mode theory results show excellent agreement with numerical solutions, proving the robustness of coupled mode theory in describing various degrees of imperfection in systems with PTS.https://doi.org/10.1088/1367-2630/18/12/125012opticsparity-time symmetrygain induced dispersion42.79.Gn42.60.Lh47.20.Ky |
| spellingShingle | Ngoc B Nguyen Stefan A Maier Minghui Hong Rupert F Oulton Recovering parity-time symmetry in highly dispersive coupled optical waveguides New Journal of Physics optics parity-time symmetry gain induced dispersion 42.79.Gn 42.60.Lh 47.20.Ky |
| title | Recovering parity-time symmetry in highly dispersive coupled optical waveguides |
| title_full | Recovering parity-time symmetry in highly dispersive coupled optical waveguides |
| title_fullStr | Recovering parity-time symmetry in highly dispersive coupled optical waveguides |
| title_full_unstemmed | Recovering parity-time symmetry in highly dispersive coupled optical waveguides |
| title_short | Recovering parity-time symmetry in highly dispersive coupled optical waveguides |
| title_sort | recovering parity time symmetry in highly dispersive coupled optical waveguides |
| topic | optics parity-time symmetry gain induced dispersion 42.79.Gn 42.60.Lh 47.20.Ky |
| url | https://doi.org/10.1088/1367-2630/18/12/125012 |
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