[ { "id": "authors:fcxy8-wn679", "collection": "authors", "collection_id": "fcxy8-wn679", "cite_using_url": "https://authors.library.caltech.edu/records/fcxy8-wn679", "type": "article", "title": "Microcavity Kerr optical frequency division with integrated SiN photonics", "author": [ { "family_name": "Sun", "given_name": "Shuman", "orcid": "0009-0005-9898-2536", "clpid": "Sun-Shuman" }, { "family_name": "Harrington", "given_name": "Mark W." }, { "family_name": "Tabatabaei", "given_name": "Fatemehsadat", "orcid": "0000-0003-1366-3658" }, { "family_name": "Hanifi", "given_name": "Samin" }, { "family_name": "Liu", "given_name": "Kaikai", "orcid": "0000-0002-1360-9646" }, { "family_name": "Wang", "given_name": "Jiawei" }, { "family_name": "Wang", "given_name": "Beichen", "orcid": "0000-0001-5443-1875" }, { "family_name": "Yang", "given_name": "Zijiao" }, { "family_name": "Liu", "given_name": "Ruxuan" }, { "family_name": "Morgan", "given_name": "Jesse S.", "orcid": "0000-0002-7845-2555" }, { "family_name": "Bowers", "given_name": "Steven M.", "orcid": "0000-0002-4243-8663" }, { "family_name": "Morton", "given_name": "Paul A.", "orcid": "0000-0003-2649-2536" }, { "family_name": "Nelson", "given_name": "Karl D." }, { "family_name": "Beling", "given_name": "Andreas" }, { "family_name": "Blumenthal", "given_name": "Daniel J.", "orcid": "0000-0002-1735-7220" }, { "family_name": "Yi", "given_name": "Xu", "orcid": "0000-0002-2485-1104" } ], "abstract": "Optical frequency division has revolutionized microwave and millimetre-wave generation and set spectral purity records owing to its unique capability to transfer high fractional stability from optical to electronic frequencies. Recently, rapid developments in integrated optical reference cavities and microresonator-based optical frequency combs (microcombs) have created a path to transform optical frequency division technology to the chip scale. Here we demonstrate an ultralow-phase-noise millimetre-wave oscillator by leveraging integrated photonic components and microcavity Kerr optical frequency division. The oscillator derives its stability from an integrated complementary-metal\u2013oxide\u2013semiconductor-compatible SiN coil cavity, and the optical frequency division is achieved spontaneously through Kerr interaction in the integrated SiN microresonator between the soliton microcombs and the injected reference lasers. Besides achieving low phase noise for integrated millimetre-wave oscillators, our demonstration greatly simplifies the implementation of integrated optical frequency division oscillators and could be useful in applications of radar, spectroscopy and astronomy.", "doi": "10.1038/s41566-025-01668-3", "issn": "1749-4885", "publisher": "Nature Publishing Group", "publication": "Nature Photonics", "publication_date": "2025-06", "series_number": "6", "volume": "19", "issue": "6", "pages": "637-642" }, { "id": "authors:pdc14-yyb85", "collection": "authors", "collection_id": "pdc14-yyb85", "cite_using_url": "https://authors.library.caltech.edu/records/pdc14-yyb85", "type": "article", "title": "Dispersive-wave-agile optical frequency division", "author": [ { "family_name": "Ji", "given_name": "Qing-Xin", "orcid": "0000-0002-6336-8350" }, { "family_name": "Zhang", "given_name": "Wei", "orcid": "0000-0003-2065-2535" }, { "family_name": "Savchenkov", "given_name": "Anatoliy" }, { "family_name": "Liu", "given_name": "Peng", "orcid": "0009-0002-1270-3240", "clpid": "Liu-Peng" }, { "family_name": "Sun", "given_name": "Shuman", "orcid": "0009-0005-9898-2536", "clpid": "Sun-Shuman" }, { "family_name": "Jin", "given_name": "Warren" }, { "family_name": "Guo", "given_name": "Joel", "orcid": "0000-0003-0203-5170" }, { "family_name": "Peters", "given_name": "Jonathan" }, { "family_name": "Wu", "given_name": "Lue", "orcid": "0000-0002-7503-7057", "clpid": "Wu-Lue" }, { "family_name": "Feshali", "given_name": "Avi" }, { "family_name": "Paniccia", "given_name": "Mario" }, { "family_name": "Ilchenko", "given_name": "Vladimir", "orcid": "0009-0002-3545-8700" }, { "family_name": "Bowers", "given_name": "John", "orcid": "0000-0003-4270-8296" }, { "family_name": "Matsko", "given_name": "Andrey", "orcid": "0000-0001-9939-9311" }, { "family_name": "Vahala", "given_name": "Kerry J.", "orcid": "0000-0003-1783-1380", "clpid": "Vahala-K-J" } ], "abstract": "The remarkable frequency stability of resonant systems in the optical domain (optical cavities and atomic transitions) can be harnessed at frequency scales accessible by electronics using optical frequency division. This capability is revolutionizing technologies spanning time keeping to high-performance electrical signal sources. A version of the technique called two-point optical frequency division (2P-OFD) is proving advantageous for application to high-performance signal sources. In 2P-OFD, an optical cavity anchors two spectral endpoints defined by lines of a frequency comb. The comb need not be self-referenced, which greatly simplifies the system architecture and reduces power requirements. Here, a 2P-OFD microwave signal source is demonstrated with record-low phase noise using a microcomb. Key to this advance is a spectral endpoint defined by a frequency-agile single-mode dispersive wave that is emitted by the microcomb soliton. Moreover, the system frequency reference is a compact all-solid-state optical cavity with a record Q factor. A hybridly packaged version of the system offers excellent longer term stability. The results advance integrable microcomb-based signal sources into the performance realm of much larger microwave sources.", "doi": "10.1038/s41566-025-01667-4", "issn": "1749-4885", "publisher": "Nature Publishing Group", "publication": "Nature Photonics", "publication_date": "2025-06", "volume": "19", "pages": "624\u2013629" } ]