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arXiv · 2608.12943

Fast and wide-range wavelength tuning of a III-V/Si3N4 external-cavity laser via two-step pulsed heating

Cong Wang·Fuyi Cao·Xin Xu·Yihan Qi·Dongxin Jiang·Masataka Kobayashi·To-Fan Pan·Zhan Su·Guoen Weng·Hidefumi Akiyama·Shaoqiang Chen
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Abstract

Fast and wide-range wavelength switching is desirable for optical communications and photonic systems that are frequency-agile. However, thermo-optic (TO)-tuned integrated lasers often have limited switching times and tuning rates. This study demonstrates a hybrid-integrated III-V/Si3N4 external-cavity laser (ECL), combining a dual-microring Vernier filter with thermal pumping to give wide-range and fast wavelength control. The ECL provides single-mode static lasing wavelength tuning in the 1486-1614 nm range. Impulsive thermal pumping that is applied through microheaters with shorter duration and higher amplitude accelerates the switching time. A simple first-order thermal fit reproduces the measurements well, indicating that the TO-tuning dynamics are highly predictable. Consequently, two-step pulse thermal pumping is applied to the on-chip microheaters to exploit the initial quasi-linear heating transient and sustain the target wavelength at a subsequent equilibrium. The results show that 101 and 104 nm red- and blue-shift switches are achieved with quasi-linear tuning rates of 8.91 and 9.68 nm/us, respectively. This approach provides a practical route toward fast wavelength switching in TO-tuned ECLs, potentially extending their applicability within frequency-agile systems, such as wavelength-division multiplexed transceivers.

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Cong Wang, Fuyi Cao, Xin Xu, Yihan Qi, Dongxin Jiang, Masataka Kobayashi, To-Fan Pan, Zhan Su, Guoen Weng, Hidefumi Akiyama, Shaoqiang Chen. 2026-08-13. Fast and wide-range wavelength tuning of a III-V/Si3N4 external-cavity laser via two-step pulsed heating. https://arxiv.org/abs/2608.12943

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