Self-aligned optical microcomb emerging between octave separated lasers

Grégory Moille; Pradyoth Shandilya; Jordan Stone; River Beard; Shao-Chien Ou; Zongda Li; Mark Harrington; Kaikai Liu; Robert Rockmore; Curtis R. Menyuk; Daniel J. Blumenthal; Sean P. Krzyzewski; Miro Erkintalo; Kartik Srinivasan

arXiv · 2602.05151

Self-aligned optical microcomb emerging between octave separated lasers

Grégory Moille·Pradyoth Shandilya·Jordan Stone·River Beard·Shao-Chien Ou·Zongda Li·Mark Harrington·Kaikai Liu·Robert Rockmore·Curtis R. Menyuk·Daniel J. Blumenthal·Sean P. Krzyzewski·Miro Erkintalo·Kartik Srinivasan

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Abstract

Optical frequency combs (OFCs) are frequency rulers essential for precision metrology, next generation navigation, and testing of fundamental physics. Despite intense efforts, chip-integrated OFCs remain laboratory-bound, unable to fulfill their promise of compact and cost-effective deployment. While improvement in fabrication and integration are important, a conceptual limitation has fundamentally stymied progress: on-chip OFC architectures have aimed to miniaturize their table-top counterparts and relied on cascading outward from (i.e., spectrally broadening) a single pump. In integrated platforms, this approach does not readily allow for the generation of strong and low-noise octave-spaced signals that are crucially needed for robust zero-frequency offset detection. Here, we overcome this limitation via an architectural inversion where an optical microcomb forms by filling the spectrum between two octave-separated pump lasers. The two pumps generate a parametrically driven cavity soliton (PDCS) in an integrated $\chi^{(3)}$ resonator, which robustly self-aligns to (i.e., synchronizes with) the pump lasers across multiple foundry-fabricated devices and operating configurations. This produces a single octave-spanning comb extending from telecom to visible wavelengths, whose zero-frequency offset is completely defined by the two harmonically-related pump lasers, and can therefore be reliably detected and stabilized. We showcase our platform's capabilities by executing all of the three core tasks of OFC metrology: optical frequency synthesis, low-noise millimeter-wave generation, and integrated optical clock readout, using the same self-aligned microcomb with only its input locks changed.

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Grégory Moille, Pradyoth Shandilya, Jordan Stone, River Beard, Shao-Chien Ou, Zongda Li, Mark Harrington, Kaikai Liu, Robert Rockmore, Curtis R. Menyuk, Daniel J. Blumenthal, Sean P. Krzyzewski, Miro Erkintalo, Kartik Srinivasan. 2026-02-05. Self-aligned optical microcomb emerging between octave separated lasers. https://arxiv.org/abs/2602.05151

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