Article
Optics
Antonio Cutrona, Maxwell Rowley, Debayan Das, Luana Olivieri, Luke Peters, Sai T. Chu, Brent E. Little, Roberto Morandotti, David J. Moss, Juan Sebastian Totero Gongora, Marco Peccianti, Alessia Pasquazi
Summary: This study theoretically and experimentally investigates the soliton conversion efficiency between the narrowband input pulse and the two outputs of a four-port integrated microcavity. It is found that the single-soliton conversion efficiencies of the broadband comb outputs are high, with a total conversion efficiency of 72% in a specific micro-ring resonator case.
Article
Optics
Krishna Twayana, Fuchuan Lei, Zhichao Ye, Israel Rebolledo-Salgado, Oskar B. Helgason, Magnus Karlsson, Victor Torres-Company
Summary: We report a linear heterodyne technique assisted by electro-optic downconversion that enables differential phase measurement of microcombs with unprecedented sensitivity and bandwidth coverage.
Article
Optics
Oskar B. Helgason, Marcello Girardi, Zhichao Ye, Fuchuan Lei, Jochen Schroder, Victor Torres-Company
Summary: Laser frequency combs are being used in various scientific applications, and dissipative Kerr solitons in microresonators offer a promising way to achieve higher power conversion efficiency. By inducing a controllable frequency shift in two linearly coupled anomalous-dispersion microresonators, researchers have demonstrated a coherent dissipative Kerr soliton with a conversion efficiency exceeding 50% and excellent line spacing stability. This opens up possibilities for practical implementation of energy-efficient integrated photonic architectures.
Article
Optics
Zheng Gong, Mohan Shen, Juanjuan Lu, Joshua B. Surya, Hong X. Tang
Summary: Hybrid Kerr and electro-optic microcombs based on a lithium niobate thin film are demonstrated, enabling direct electronic detection and feedback control of terahertz soliton repetition rates by interleaving high-repetition-rate Kerr soliton comb with low-repetition-rate electro-optic comb on the same waveguide.
Article
Optics
Yong Geng, Xinjie Han, XiaoXu Zhang, Yanlan Xiao, Sirong Qian, Qingsong Bai, Yunru Fan, Guangwei Deng, Qiang Zhou, Kun Qiu, Jing Xu, Heng Zhou
Summary: This Letter presents a detailed experimental investigation on the phase coherence between two on-chip Kerr soliton microcombs and analyzes the physical and technical origins of the mutual phase noise between the microcombs. The techniques of 2-point locking and optical frequency division are explored to enhance the dual-microcomb phase coherence.
Article
Multidisciplinary Sciences
Chao Xiang, Junqiu Liu, Joel Guo, Lin Chang, Rui Ning Wang, Wenle Weng, Jonathan Peters, Weiqiang Xie, Zeyu Zhang, Johann Riemensberger, Jennifer Selvidge, Tobias J. Kippenberg, John E. Bowers
Summary: Silicon photonics enables integration of optical functionalities on chip, and our approach of heterogeneously integrated laser soliton microcombs provides a route for large-volume, low-cost manufacturing of chip-based frequency combs. These devices can output single-soliton microcombs with a 100-gigahertz repetition rate and offer laser frequency noise reduction, showing potential for next-generation high-capacity transceivers, data centers, and mobile platforms.
Article
Optics
T. uo l Iu, S. uwan s Un, S. iyu w Ang, Y. ongyuan c Hu, H. airun g Uo
Summary: This study demonstrates soliton microcombs with broadband and dispersive intermode interactions in homedeveloped magnesium fluoride microresonators. The authors observed comb states with broadband spectral tailoring effect via an intermode pumping scheme, and identified footprints of both constructive and destructive interference on the comb spectrum.
PHOTONICS RESEARCH
(2022)
Article
Optics
Hao Liu, Shu-Wei Huang, Wenting Wang, Jinghui Yang, Mingbin Yu, Dim-Lee Kwong, Pierre Colman, Chee Wei Wong
Summary: Significant progress has been made in the generation of dissipative Kerr solitons in chip-scale nonlinear resonators, offering a wide range of applications. In this study, square pulse formation in the normal dispersion regime is achieved, and its tuning is demonstrated through modulation frequency. Experimental and modeling results confirm the observation of platicon pulses with different widths.
PHOTONICS RESEARCH
(2022)
Article
Multidisciplinary Sciences
Wenle Weng, Aleksandra Kaszubowska-Anandarajah, Jijun He, Prajwal D. Lakshmijayasimha, Erwan Lucas, Junqiu Liu, Prince M. Anandarajah, Tobias J. Kippenberg
Summary: The authors have successfully generated dissipative Kerr solitons with stable repetition rates and low optical power threshold by actively switching the bias current of injection-locked III-V semiconductor lasers and pulse-pumping crystalline and integrated microresonators.
NATURE COMMUNICATIONS
(2021)
Review
Optics
Yang Sun, Jiayang Wu, Mengxi Tan, Xingyuan Xu, Yang LI, Roberto Morandotti, Arnan Mitchell, David J. MOss
Summary: Optical microcombs are compact chip-scale devices that generate laser frequency combs, which have supported many technological advances in fundamental science and industrial applications. Their applications have rapidly progressed in the past decade, not only in traditional fields such as frequency synthesis, signal processing, and optical communications, but also in interdisciplinary fields including LiDAR, astronomical detection, neuromorphic computing, and quantum optics.
ADVANCES IN OPTICS AND PHOTONICS
(2023)
Article
Optics
Zong-Ren Yang, Pei-Hsun Wang
Summary: We theoretically investigate the stability of mode-coupling-assisted frequency comb generation in normal-dispersion microresonators. Our analysis quantitatively explores the modulational instability in the parameter space of pump power and detuning by considering the coupled mode number, dispersion, and coupling strength in the normalized Lugiato-Lefever model. We find that modulational stability gain exists, leading to extended spatial structures within the regime of eigenvalue bifurcations. Additionally, we discuss the dynamics and efficiency of microcombs, providing guidelines for high-efficient, stable, and controllable combs in a normal-dispersion system.
Article
Optics
Zhichao Ye, Fuchuan Lei, Krishna Twayana, Marcello Girardi, Peter A. Andrekson, Victor Torres-Company
Summary: The generation of sub-50GHz soliton microcombs in dispersion-engineered silicon nitride microresonators has been achieved by implementing an optimized racetrack design, minimizing coupling to higher-order modes and reducing the footprint size significantly. These devices feature a statistical intrinsic quality factor of 19 million and have successfully generated soliton microcombs at repetition rates of 20.5 and 14.0 GHz. The fabrication process is entirely subtractive, allowing direct patterning on the silicon nitride film.
LASER & PHOTONICS REVIEWS
(2022)
Article
Optics
Ruolan Wang, Liao Chen, Hao Hu, Yanjing Zhao, Chi Zhang, Wenfu Zhang, Xinliang Zhang
Summary: This study presents a scheme for measuring the RF spectrum of microcombs using an FP-assisted LISA analyzer, achieving higher precision through compensating for extra dispersion. The research records the RF comb variation characteristics of microcombs in different states, providing insights into the physical mechanism of microcombs. The improved bandwidth and resolution of the FP-assisted LISA enable more precise measurement of RF spectrum.
Article
Optics
Jonathan Musgrave, Shu-Wei Huang, Mingming Nie
Summary: Optical frequency combs, especially microcombs generated from fiber Fabry-Perot microresonators, have significant applications in science and technology. They offer compact size, low cost, high-energy efficiency, and large comb spacing, making them attractive for various fields.
Article
Optics
Shuai Wan, Rui Niu, Jin-Lan Peng, Jin Li, Guang-Can Guo, Chang-Ling Zou, Chun-Hua Dong
Summary: In this work, Si3N4 microring resonators were fabricated for soliton microcomb generation. By developing a fabrication process with crack isolation trenches and annealing, high-quality Si3N4 films were deposited without cracks, resulting in a high intrinsic Q of 6 x 10(6) and low propagation loss of 0.058 dBm/cm. With these microrings, soliton microcombs were generated using 100 mW on-chip pump power, with an optical parametric oscillation threshold of only 13.4 mW. The Si3N4 integrated chip provides an ideal platform for nonlinear photonics and integrated photonics research and applications.
CHINESE OPTICS LETTERS
(2022)
Article
Mathematics, Interdisciplinary Applications
Mansour Eslami, Maryam Kanafchian, Gian-Luca Oppo
Summary: In this study, oscillating and chaotic regimes of honeycomb patterns and dark cavity solitons were examined in a cavity displaying electromagnetically induced transparency. The numerical investigation of the transition to chaotically oscillating honeycombs in a three-level atomic system revealed the dynamical behavior for different control parameter values. It was found that oscillating dark cavity solitons coexist with the honeycomb patterns. The coherent oscillation of these solitons was achieved by selecting an appropriate separation distance, leading to the discovery of a novel regime of chimera states.
CHAOS SOLITONS & FRACTALS
(2023)
Article
Optics
X. I. A. O. T. I. A. N. ZHU, G. U. A. N. G. K. U. O. LI, X. I. A. N. G. WANG, Y. U. H. U. A. LI, R. O. Y. DAVIDSON, B. R. E. N. T. E. LITTLE, S. A. I. T. CHU
Summary: Silicon nitride (SiN) integrated optical waveguides, known for their low loss, wide bandwidth, and high nonlinearity, face a challenge when coupling with single-mode fibers due to mode mismatch. In this study, we propose a coupling approach using high-index doped silica glass (HDSG) waveguides as intermediaries to address this issue. Our approach achieves a fiber-to-SiN waveguide coupling efficiency of lower than 0.8 dB/facet across the full C and L bands, while maintaining high fabrication and alignment tolerances.
Review
Optics
Yang Sun, Jiayang Wu, Mengxi Tan, Xingyuan Xu, Yang LI, Roberto Morandotti, Arnan Mitchell, David J. MOss
Summary: Optical microcombs are compact chip-scale devices that generate laser frequency combs, which have supported many technological advances in fundamental science and industrial applications. Their applications have rapidly progressed in the past decade, not only in traditional fields such as frequency synthesis, signal processing, and optical communications, but also in interdisciplinary fields including LiDAR, astronomical detection, neuromorphic computing, and quantum optics.
ADVANCES IN OPTICS AND PHOTONICS
(2023)
Article
Optics
Baoshuai Li, Weiqiang Wang, Honglei Yang, Hao Liu, Sai T. Chu, Brent Little, Yuxia Song, Boren Guan, Wenfu Zhang, Mingyu Li
Summary: We demonstrate a hybrid integrated laser based on an optical negative feedback scheme, which consists of a commercial distributed feedback (DFB) laser diode and an on-chip micro-resonator with a Q-factor of 0.815 million. By coupling the feedback optical field back to the laser cavity through the back facet, the laser maintains the lasing efficiency of the DFB laser diode and compresses its linewidth from 2 MHz to 6 kHz, corresponding to a linewidth reduction factor of 25.2 dB. Theoretical analysis suggests that precise control of the detuning between laser frequency and the micro-resonator, as well as the phase delay of the feedback optical field, could further improve the laser performance. This hybrid narrow-linewidth laser diode has wide application prospects in coherent optical systems due to its low cost and high volume productivity.
Article
Physics, Applied
A. Cutrona, M. Rowley, A. Bendahmane, V. Cecconi, L. Peters, L. Olivieri, B. E. Little, S. T. Chu, S. Stivala, R. Morandotti, D. J. Moss, J. S. Totero Gongora, M. Peccianti, A. Pasquazi
Summary: A detailed study on the free-running stability properties of single solitons is presented, which are the most suitable states for developing robust ultrafast and high repetition rate comb sources. The carrier frequency and repetition rate can be controlled by modulating the laser pump current and the cavity length, providing a path for active locking and long-term stabilization.
APPLIED PHYSICS LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Xingyuan Xu, Weiwei Han, Mengxi Tan, Yang Sun, Yang Li, Jiayang Wu, Roberto Morandotti, Arnan Mitchell, Kun Xu, David J. Moss
Summary: Optical neural networks (ONNs) based on wavelength-division multiplexing (WDM) techniques offer high bandwidth and analog architecture for enhanced computing power and energy efficiency. Integrated microcombs have been used to implement ONNs, with successful applications such as optical convolution accelerators for human image processing at 11 Tera operations per second. However, challenges and limitations of ONNs still need to be addressed for future applications.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2023)
Article
Optics
Xinyu Wang, Wei-qiang Wang, Peng Xie, Yang Wang, Sai T. Chu, Brent. E. Little, Wei Zhao, Wen-fu Zhang
Summary: This study demonstrates a new approach for deterministic single soliton generation in a microresonator. By pumping the microresonator at a mode with a frequency shift of -160 MHz, a native mode spaced (NMS) Turing pattern is formed, providing a potential field to capture and sustain single solitons. The stable and deterministic single soliton micro-comb formation achieved in this experiment paves a new way for practical applications.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Yang Sun, Jiayang Wu, Yang Li, Mengxi Tan, Xingyuan Xu, Sai Tak Chu, Brent E. Little, Roberto Morandotti, Arnan Mitchell, David J. Moss
Summary: Photonic RF transversal signal processors, implemented with photonic technologies, offer high-speed information processing with reduced size, power consumption, and complexity. Optical microcombs generated from compact micro-resonators are ideal sources for RF photonics. This study provides a detailed analysis of the processing accuracy of microcomb-based photonic RF transversal signal processors. Theoretical limitations, practical error sources, and the relative contributions of both are investigated, highlighting the potential for further error reduction through feedback control.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2023)
Article
Engineering, Chemical
Ting Si, Xinyao Ma, Tairan Wang, Sai Tak Chu, Jun Fan
Summary: Due to its large surface area, rich termination groups, and good electrical properties, MXene is considered as one of the most promising 2D materials for seawater desalination. The optimization strategy of MXene membranes has been a current research focus. This paper proposes a new method for optimizing membranes by investigating the arrangement of homogeneous MXene membranes using molecular dynamics simulation. The results show that the arrangement of heterogeneous MXene membranes improves desalination performance, providing a new membrane strategy for better desalination performance.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Bennet Fischer, Mario Chemnitz, Yi Zhu, Nicolas Perron, Piotr Roztocki, Benjamin Maclellan, Luigi Di Lauro, A. Aadhi, Cristina Rimoldi, Tiago H. Falk, Roberto Morandotti
Summary: This study presents an implementation of neuromorphic wave computing using broadband frequency conversion in a single-mode fiber. The results show that through phase encoding and frequency selection and weighting, energy-efficient emulation of various digital neural networks is possible. The experiments demonstrate an enhancement in computational performance with increasing system nonlinearity. The findings also suggest that broadband frequency generation accessible on-chip and in-fiber may challenge traditional approaches to brain-inspired hardware design, leading to energy-efficient and scalable computing.
Article
Physics, Multidisciplinary
Lewis Hill, Gian-Luca Oppo, Pascal Del'Haye
Summary: This work presents the multi-stage symmetry breaking in ring resonators with Kerr nonlinearity, which has potential applications in photonic circuits and optical communications. The results show that the multi-stage symmetry breaking naturally occurs in a resonator with bidirectionally propagating light with orthogonal polarization components.
COMMUNICATIONS PHYSICS
(2023)
Article
Optics
Mark Anthony Carroll, Giampaolo D'Alessandro, Gian Luca Lippi, Gian-Luca Oppo, Francesco Papoff
Summary: We derive nanolaser models that include coherent and incoherent variables and predict the existence of a laser threshold for both single- and multielectron systems. The increase in correlation between absorption and emission processes leads to self-sustained stimulated emission and the dominance of coherent emission. The first-order coherence increases steadily and reaches unity at or beyond threshold, while the transition towards coherent emission becomes sharper with increasing numbers of emitters and cavity modes.
Article
Physics, Multidisciplinary
G. R. M. Robb, J. G. M. Walker, G. -L. Oppo, T. A. Ackemann
Summary: A Bose-Einstein condensate (BEC) interacting with an optical field via a feedback mirror can realize the quantum Hamiltonian Mean Field (HMF) model, which is a typical model for long-range interactions in quantum systems. It has been shown that the self-structuring instability of a initially uniform BEC can evolve in accordance with the predictions of the quantum HMF model, exhibiting quasiperiodic chevron dynamics under strong driving. Under weak driving, the BEC and optical field behave as a two-state quantum system, oscillating regularly between a spatially uniform state and a spatially periodic state. This study also predicts the width of stable optomechanical droplets and their dependence on optical pump intensity.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Optics
Caleb Todd, Zongda Li, Stuart G. Murdoch, Gian-Luca Oppo, Miro Erkintalo
Summary: Temporal Kerr cavity solitons are light pulses that can exist in coherently driven, dispersive resonators with Kerr-type nonlinearity. Previous studies have assumed that the inhomogeneity of the driving field varies slowly across the soliton, leading to linear soliton drift rate. However, in some cases, such as using bichromatic driving or in the presence of third-order dispersion, the assumption of slowly varying inhomogeneity may not hold true.
