Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap
Cavity optomechanics has recently emerged as a new paradigm enabling the manipulation of mechanical motion via optical fields tightly confined in deformable cavities. When driving an optomechanical (OM) crystal cavity with a laser blue-detuned with respect to the optical resonance, the mechanical mo...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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De Gruyter
2020-07-01
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| Series: | Nanophotonics |
| Subjects: | |
| Online Access: | https://doi.org/10.1515/nanoph-2020-0148 |
| _version_ | 1828933494611378176 |
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| author | Mercadé Laura Martín Leopoldo L. Griol Amadeu Navarro-Urrios Daniel Martínez Alejandro |
| author_facet | Mercadé Laura Martín Leopoldo L. Griol Amadeu Navarro-Urrios Daniel Martínez Alejandro |
| author_sort | Mercadé Laura |
| collection | DOAJ |
| description | Cavity optomechanics has recently emerged as a new paradigm enabling the manipulation of mechanical motion via optical fields tightly confined in deformable cavities. When driving an optomechanical (OM) crystal cavity with a laser blue-detuned with respect to the optical resonance, the mechanical motion is amplified, ultimately resulting in phonon lasing at MHz and even GHz frequencies. In this work, we show that a silicon OM crystal cavity performs as an OM microwave oscillator when pumped above the threshold for self-sustained OM oscillations. To this end, we use an OM cavity designed to have a breathing-like mechanical mode at 3.897 GHz in a full phononic bandgap. Our measurements show that the first harmonic of the detected signal displays a phase noise of ≈−100 dBc/Hz at 100 kHz. Stronger blue-detuned driving leads eventually to the formation of an OM frequency comb, whose lines are spaced by the mechanical frequency. We also measure the phase noise for higher-order harmonics and show that, unlike in Brillouin oscillators, the noise is increased as corresponding to classical harmonic mixing. Finally, we present real-time measurements of the comb waveform and show that it can be fitted to a theoretical model recently presented. Our results suggest that silicon OM cavities could be relevant processing elements in microwave photonics and optical RF processing, in particular in disciplines requiring low weight, compactness and fiber interconnection. |
| first_indexed | 2024-12-14T01:16:13Z |
| format | Article |
| id | doaj.art-5123ab2c9379481a880f18ebe3de5818 |
| institution | Directory Open Access Journal |
| issn | 2192-8606 2192-8614 |
| language | English |
| last_indexed | 2024-12-14T01:16:13Z |
| publishDate | 2020-07-01 |
| publisher | De Gruyter |
| record_format | Article |
| series | Nanophotonics |
| spelling | doaj.art-5123ab2c9379481a880f18ebe3de58182022-12-21T23:22:34ZengDe GruyterNanophotonics2192-86062192-86142020-07-019113535354410.1515/nanoph-2020-0148Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgapMercadé Laura0Martín Leopoldo L.1Griol Amadeu2Navarro-Urrios Daniel3Martínez Alejandro4Nanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, SpainNanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, SpainNanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, SpainMIND-IN2UB, Departament d’Enginyeria Electrònica i Biomèdica, Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, SpainNanophotonics Technology Center, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, SpainCavity optomechanics has recently emerged as a new paradigm enabling the manipulation of mechanical motion via optical fields tightly confined in deformable cavities. When driving an optomechanical (OM) crystal cavity with a laser blue-detuned with respect to the optical resonance, the mechanical motion is amplified, ultimately resulting in phonon lasing at MHz and even GHz frequencies. In this work, we show that a silicon OM crystal cavity performs as an OM microwave oscillator when pumped above the threshold for self-sustained OM oscillations. To this end, we use an OM cavity designed to have a breathing-like mechanical mode at 3.897 GHz in a full phononic bandgap. Our measurements show that the first harmonic of the detected signal displays a phase noise of ≈−100 dBc/Hz at 100 kHz. Stronger blue-detuned driving leads eventually to the formation of an OM frequency comb, whose lines are spaced by the mechanical frequency. We also measure the phase noise for higher-order harmonics and show that, unlike in Brillouin oscillators, the noise is increased as corresponding to classical harmonic mixing. Finally, we present real-time measurements of the comb waveform and show that it can be fitted to a theoretical model recently presented. Our results suggest that silicon OM cavities could be relevant processing elements in microwave photonics and optical RF processing, in particular in disciplines requiring low weight, compactness and fiber interconnection.https://doi.org/10.1515/nanoph-2020-0148microwave oscillatoroptical frequency comboptomechanical crystal cavityphononic bandgapsilicon photonics |
| spellingShingle | Mercadé Laura Martín Leopoldo L. Griol Amadeu Navarro-Urrios Daniel Martínez Alejandro Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap Nanophotonics microwave oscillator optical frequency comb optomechanical crystal cavity phononic bandgap silicon photonics |
| title | Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap |
| title_full | Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap |
| title_fullStr | Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap |
| title_full_unstemmed | Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap |
| title_short | Microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap |
| title_sort | microwave oscillator and frequency comb in a silicon optomechanical cavity with a full phononic bandgap |
| topic | microwave oscillator optical frequency comb optomechanical crystal cavity phononic bandgap silicon photonics |
| url | https://doi.org/10.1515/nanoph-2020-0148 |
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