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arXiv · 2510.15146

Chip-scale ultrafast soliton laser

Qili Hu·Raymond Lopez-Rios·Zhengdong Gao·Jingwei Ling·Shixin Xue·Jeremy Staffa·Yang He·Qiang Lin
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Abstract

Femtosecond laser, owing to their ultrafast time scales and broad frequency bandwidths, have substantially changed fundamental science over the past decades, from chemistry and bio-imaging to quantum physics. Critically, many emerging industrial-scale photonic technologies -- such as optical interconnects, AI accelerators, quantum computing, and LiDAR -- also stand to benefit from their massive frequency parallelism. However, achieving a femtosecond-scale laser on-chip, constrained by size and system power input, has remained a long-standing challenge. Here, we demonstrate the first on-chip femtosecond laser, enabled by a new mechanism -- photorefraction-assisted soliton (PAS) mode-locking. Operating from a simple, low-voltage electrical supply, the laser provides deterministic, turn-key generation of sub-90-fs solitons. Furthermore, it provides electronic reconfigurability of its pulse properties and features an exceptional optical coherence with a 53 Hz intrinsic comb linewidth. This demonstration removes a key barrier to the full integration of chip-scale photonic systems for next-generation sensing, communication, metrology, and computing.

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Qili Hu, Raymond Lopez-Rios, Zhengdong Gao, Jingwei Ling, Shixin Xue, Jeremy Staffa, Yang He, Qiang Lin. 2025-10-16. Chip-scale ultrafast soliton laser. https://arxiv.org/abs/2510.15146

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