TY - JOUR
T1 - Tunable amplitude and frequency modulated optical frequency combs in external-cavity-locked quantum dot lasers
AU - Wang, Wenlu
AU - Duan, Jianan
AU - Ding, Shihao
AU - Yang, Bo
AU - Cui, Xiangru
AU - Meng, Xin
AU - Shi, Mingzhao
AU - Huang, Heming
AU - Zhao, Shiyuan
AU - He, Feng
AU - Wang, Jiawei
AU - Xu, Xiaochuan
AU - Yao, Yong
AU - Wang, Zihao
AU - Wang, Ting
AU - Zhang, Jianjun
AU - Grillot, Frédéric
N1 - Publisher Copyright:
© The Authors. Published by SPIE and CLP under a Creative Commons Attribution 4.0 International License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.
PY - 2025/11/1
Y1 - 2025/11/1
N2 - Optical frequency combs (OFCs) are highly promising candidates as multichannel light sources for photonic integrated circuits (PICs). We present a tunable on-chip OFC source based on quantum dot colliding-pulse mode-locked lasers (QD-CPMLs), capable of generating both amplitude-modulated (AM) and frequency-modulated (FM) combs through external-cavity locking. A free-running fourth-order QD-CPML with a 100 GHz repetition rate is demonstrated to produce FM and AM combs under different bias conditions, achieving an ultra-wide comb with a 3-dB bandwidth of 1.8 THz and a 10-dB bandwidth of 2.5 THz. By leveraging external-cavity locking, the modulation dynamics of the comb are finely tuned, significantly expanding the AM comb range while reducing pulse width and chirp. The shortest pulse width achieved is 0.6 ps, with a minimum time-bandwidth product of 0.33, approaching the transform limit for hyperbolic secant pulses. The near-zero linewidth enhancement factor of the QD-CPML effectively suppresses coherence collapse under optical feedback, whereas its low group velocity dispersion facilitates the generation of narrow pulses and broad bandwidths. The ability to dynamically control AM and FM comb regions through external-cavity locking represents an innovative strategy for tunable OFC generation, offering potential for applications in sensing, spectroscopy, and optical communications within PICs.
AB - Optical frequency combs (OFCs) are highly promising candidates as multichannel light sources for photonic integrated circuits (PICs). We present a tunable on-chip OFC source based on quantum dot colliding-pulse mode-locked lasers (QD-CPMLs), capable of generating both amplitude-modulated (AM) and frequency-modulated (FM) combs through external-cavity locking. A free-running fourth-order QD-CPML with a 100 GHz repetition rate is demonstrated to produce FM and AM combs under different bias conditions, achieving an ultra-wide comb with a 3-dB bandwidth of 1.8 THz and a 10-dB bandwidth of 2.5 THz. By leveraging external-cavity locking, the modulation dynamics of the comb are finely tuned, significantly expanding the AM comb range while reducing pulse width and chirp. The shortest pulse width achieved is 0.6 ps, with a minimum time-bandwidth product of 0.33, approaching the transform limit for hyperbolic secant pulses. The near-zero linewidth enhancement factor of the QD-CPML effectively suppresses coherence collapse under optical feedback, whereas its low group velocity dispersion facilitates the generation of narrow pulses and broad bandwidths. The ability to dynamically control AM and FM comb regions through external-cavity locking represents an innovative strategy for tunable OFC generation, offering potential for applications in sensing, spectroscopy, and optical communications within PICs.
KW - external cavity locking
KW - quantum dot lasers
KW - tunable optical frequency comb source
UR - https://www.scopus.com/pages/publications/105026339962
U2 - 10.1117/1.AP.7.6.066011
DO - 10.1117/1.AP.7.6.066011
M3 - Article
AN - SCOPUS:105026339962
SN - 2577-5421
VL - 7
JO - Advanced Photonics
JF - Advanced Photonics
IS - 6
M1 - 066011
ER -