超低損失光ファイバー性能をフォトニックチップへ拡張 (Extending Optical Fiber’s Ultralow Loss Performance to Photonic Chips)

2026-02-04 カリフォルニア工科大学（Caltech）

Combining the low-loss performance of optical fibers with large-scale integrated circuits, the new work moves toward a new generation of ultralow-loss photonic integrated circuits.Credit: Hao-Jing Chen

＜関連情報＞

• https://www.caltech.edu/about/news/extending-optical-fibers-ultralow-loss-performance-to-photonic-chips
• https://www.nature.com/articles/s41586-025-09889-w

紫から近赤外までの光子集積における光ファイバーのような損失に向けて Towards fibre-like loss for photonic integration from violet to near-infrared

Hao-Jing Chen,Kellan Colburn,Peng Liu,Hongrui Yan,Hanfei Hou,Jinhao Ge,Jin-Yu Liu,Phineas Lehan,Qing-Xin Ji,Zhiquan Yuan,Dirk Bouwmeester,Christopher Holmes,James Gates,Henry Blauvelt & Kerry Vahala
Mature  Published:07 January 2026
DOI:https://doi.org/10.1038/s41586-025-09889-w

Abstract

Over the past decades, remarkable progress has been made in reducing the loss of photonic integrated circuits (PICs) within the telecom band^1,2,3,4, facilitating on-chip applications spanning low-noise optical⁵ and microwave synthesis⁶, to lidar⁷ and photonic artificial intelligence engines⁸. However, several obstacles arise from the marked increase in material absorption and scattering losses at shorter wavelengths^9,10, which prominently elevate power requirements and limit performance in the visible and near-visible spectrum. Here we present an ultralow-loss PIC platform based on germano-silicate—the material underlying the extraordinary performance of optical fibre—but realized by a fully CMOS-foundry-compatible process. These PICs achieve resonator Q factors surpassing 180 million from violet to telecom wavelengths. They also attain a 10-dB higher quality factor without thermal treatment in the telecom band, expanding opportunities for heterogeneous integration with active components¹¹. Other features of this platform include readily engineered waveguide dispersion, acoustic mode confinement and large-mode-area-induced thermal stability—each demonstrated by soliton microcomb generation, stimulated Brillouin lasing and low-frequency-noise self-injection locking, respectively. The success of these germano-silicate PICs can ultimately enable fibre-like loss onto a chip, leading to an additional 20-dB improvement in waveguide loss over the current highest performance photonic platforms. Moreover, the performance abilities demonstrated here bridge ultralow-loss PIC technology to optical clocks¹², precision navigation systems¹³ and quantum sensors¹⁴.