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Parity-time–symmetric optoelectronic oscillator
An optoelectronic oscillator (OEO) is a hybrid microwave and photonic system incorporating an amplified positive feedback loop to enable microwave oscillation to generate a high-frequency and low–phase noise microwave signal. The low phase noise is ensured by the high Q factor of the feedback loop e...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Association for the Advancement of Science
2018
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5993476/ https://www.ncbi.nlm.nih.gov/pubmed/29888325 http://dx.doi.org/10.1126/sciadv.aar6782 |
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author | Zhang, Jiejun Yao, Jianping |
author_facet | Zhang, Jiejun Yao, Jianping |
author_sort | Zhang, Jiejun |
collection | PubMed |
description | An optoelectronic oscillator (OEO) is a hybrid microwave and photonic system incorporating an amplified positive feedback loop to enable microwave oscillation to generate a high-frequency and low–phase noise microwave signal. The low phase noise is ensured by the high Q factor of the feedback loop enabled by the use of a long and low-loss optical fiber. However, an OEO with a long fiber loop would have a small free spectral range, leading to a large number of closely spaced oscillation modes. To ensure single-mode oscillation, an ultranarrowband optical filter must be used, but such an optical filter is hard to implement and the stability is poor. Here, we use a novel concept to achieve single-mode oscillation without using an ultranarrowband optical filter. The single-mode operation is achieved based on parity-time (PT) symmetry by using two identical feedback loops, with one having a gain and the other having a loss of the same magnitude. The operation is analyzed theoretically and verified by an experiment. Stable single-mode oscillation at an ultralow phase noise is achieved without the use of an ultranarrowband optical filter. The use of PT symmetry in an OEO overcomes the long-existing mode-selection challenge that would greatly simplify the implementation of OEOs for ultralow–phase noise microwave generation. |
format | Online Article Text |
id | pubmed-5993476 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | American Association for the Advancement of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-59934762018-06-10 Parity-time–symmetric optoelectronic oscillator Zhang, Jiejun Yao, Jianping Sci Adv Research Articles An optoelectronic oscillator (OEO) is a hybrid microwave and photonic system incorporating an amplified positive feedback loop to enable microwave oscillation to generate a high-frequency and low–phase noise microwave signal. The low phase noise is ensured by the high Q factor of the feedback loop enabled by the use of a long and low-loss optical fiber. However, an OEO with a long fiber loop would have a small free spectral range, leading to a large number of closely spaced oscillation modes. To ensure single-mode oscillation, an ultranarrowband optical filter must be used, but such an optical filter is hard to implement and the stability is poor. Here, we use a novel concept to achieve single-mode oscillation without using an ultranarrowband optical filter. The single-mode operation is achieved based on parity-time (PT) symmetry by using two identical feedback loops, with one having a gain and the other having a loss of the same magnitude. The operation is analyzed theoretically and verified by an experiment. Stable single-mode oscillation at an ultralow phase noise is achieved without the use of an ultranarrowband optical filter. The use of PT symmetry in an OEO overcomes the long-existing mode-selection challenge that would greatly simplify the implementation of OEOs for ultralow–phase noise microwave generation. American Association for the Advancement of Science 2018-06-08 /pmc/articles/PMC5993476/ /pubmed/29888325 http://dx.doi.org/10.1126/sciadv.aar6782 Text en Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). http://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license (http://creativecommons.org/licenses/by-nc/4.0/) , which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. |
spellingShingle | Research Articles Zhang, Jiejun Yao, Jianping Parity-time–symmetric optoelectronic oscillator |
title | Parity-time–symmetric optoelectronic oscillator |
title_full | Parity-time–symmetric optoelectronic oscillator |
title_fullStr | Parity-time–symmetric optoelectronic oscillator |
title_full_unstemmed | Parity-time–symmetric optoelectronic oscillator |
title_short | Parity-time–symmetric optoelectronic oscillator |
title_sort | parity-time–symmetric optoelectronic oscillator |
topic | Research Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5993476/ https://www.ncbi.nlm.nih.gov/pubmed/29888325 http://dx.doi.org/10.1126/sciadv.aar6782 |
work_keys_str_mv | AT zhangjiejun paritytimesymmetricoptoelectronicoscillator AT yaojianping paritytimesymmetricoptoelectronicoscillator |