Article
Optics
Hao Xu, Haitao Wu, Dong Hou, Haoyuan Lu, Zhaolong Li, Jianye Zhao
Summary: This article discusses the importance of higher sensitivity in timing jitter measurement and presents a method to suppress timing jitter noise using a phase error signal. The authors demonstrate a very low timing jitter noise floor between two mode-locked lasers and suggest that the method can be further extended to achieve higher timing jitter resolution.
Review
Engineering, Electrical & Electronic
Amit Yadav, Nikolai B. Chichkov, Eugene A. Avrutin, Andrei Gorodetsky, Edik U. Rafailov
Summary: Edge-emitting mode-locked quantum-dot (QD) lasers are compact, efficient sources for picosecond and femtosecond pulses and/or broad frequency combs, with direct electrical control and small footprints. Their broad gain bandwidths allow for wavelength-tuning and generation of short laser pulses over a wide range. In recent years, mode-locked QD lasers have been promising tools for low-power applications in ultrafast photonics.
PROGRESS IN QUANTUM ELECTRONICS
(2023)
Article
Physics, Multidisciplinary
Chengying Bao, Myoung-Gyun Suh, Boqiang Shen, Kemal Safak, Anan Dai, Heming Wang, Lue Wu, Zhiquan Yuan, Qi-Fan Yang, Andrey B. Matsko, Franz X. Kaertner, Kerry J. Vahala
Summary: Studies have found that coherently pumped solitons in an ideal optical microcavity exhibit weak interaction and common-mode suppression of quantum fluctuations when they are counter-propagating, while co-propagating solitons show relative timing jitter well below the quantum limit due to their strong correlation of mutual motion. The experimental results are in good agreement with theory, establishing the fundamental limits to timing jitter in soliton microcombs and providing new insights on multisoliton physics.
Article
Optics
Zhongliang Qiao, Xiang Li, Jia XuBrian Sia, WanJun Wang, Hong Wang, Lin Li, Zaijin Li, Zhibin Zhao, Guojun Liu, Hao Chen, Yi Qu, Xin Gao, Baoxue Bo, Chongyang Liu
Summary: This study utilizes double quantum wells passively mode locked lasers to achieve subpicosecond pulse generation, finding that operational parameters have significant effects on the mode-locking characteristics of the laser, especially temperature causing an increase in pulse width. This has important implications for improving the performance of the laser.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Fuchuan Lei, Zhichao Ye, Oskar B. Helgason, Attila Fulop, Marcello Girardi, Victor Torres-Company
Summary: The authors study the phase noise dynamics and linewidth of soliton microcombs and find that some comb lines can have less noise than the pump laser itself. This work not only provides insights into the physical limits of phase coherence in soliton microcombs but also demonstrates a new strategy for generating spectrally coherent light on chip.
NATURE COMMUNICATIONS
(2022)
Article
Optics
Stijn Cuyvers, Bahawal Haq, Camiel Op de Beeck, Stijn Poelman, Artur Hermans, Zheng Wang, Agnieszka Gocalinska, Emanuele Pelucchi, Brian Corbett, Gunther Roelkens, Kasper Van Gasse, Bart Kuyken
Summary: Research shows that leveraging ultra-low losses of silicon-nitride waveguides to manufacture a III-V-on-silicon-nitride integrated optical comb laser leads to superior performance, high efficiency, and low manufacturing costs.
LASER & PHOTONICS REVIEWS
(2021)
Article
Optics
Jiaqiang Lin, Zhipeng Dong, Tianhao Dong, Xuexiao Ma, Chuansheng Dai, Peijun Yao, Chun Gu, Lixin Xu
Summary: In this study, an all-fiber bidirectional mode-locked laser based on nonlinear multimode interference is reported. It can generate asynchronous pulse trains in different directions and operate in different states. This work provides a new platform for studying the dynamic characteristics of bidirectional mode-locked lasers.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Optics
Chen Liu, Liang Xu, Lei Zhang, Danlu Wang, Ziyu Cao, Zheng Zhang, Chi Zhang, Xinliang Zhang
Summary: Dual-comb spectroscopy allows for precise optical measurements, but relies on stable light sources. This study uses passive notch filtering and online calibration techniques to eliminate fluctuations and timing jitter, achieving high resolution and stability. The application of this low-cost and convenient scheme can greatly enhance the effectiveness of dual-comb spectroscopy systems.
Review
Chemistry, Multidisciplinary
Frederic Grillot, Weng W. Chow, Bozhang Dong, Shihao Ding, Heming Huang, John Bowers
Summary: Quantum dot lasers based on silicon are discussed in this paper for their advantages in passive mode-locking applications. The conditions for frequency comb and pulse train formation are quantitatively described and the mode locking process is explained. The path to achieve transform-limited performance is discussed and compared with experimental results. The impact of linewidth enhancement on performance is investigated, along with the self-consistent explanation of multimode interactions in the locking mechanism.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Electrical & Electronic
Mohammad Heydari, Aref Rasoulzadeh Zali, Reza Esmailpour Gildeh, Ali Farmani
Summary: In this study, the structure of quantum dot passively mode-locked lasers (QDMLLs) with colliding-pulse mode-locked (CPM) method was investigated to enhance its performance for ultrahigh-bit-rate compared to self-colliding pulse mode-locking (SCPM) method. Through numerical simulations, it was found that the bit rate in the CPM structure is twice that of the SCPM structure, and the grating coupling factor (GCF) changes were shown to affect the laser output power from pulsed to continuous wave operation within a certain range.
IEEE SENSORS JOURNAL
(2022)
Review
Engineering, Electrical & Electronic
Behzad Razavi
Summary: This paper investigates the basic relationship between jitter and power consumption, highlighting potential severe issues when jitters fall below 10 fs. It also suggests that clock generation in analog-to-digital converters may consume more power than the converter itself.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2021)
Article
Engineering, Electrical & Electronic
Yujia Li, Dongmei Huang, Hongjie Chen, Feng Li, P. K. A. Wai
Summary: This study investigates the statistical properties of phase noise in a swept source-based coherent detection system (CDS) using a Fourier domain mode locked (FDML) laser, both theoretically and experimentally. The study finds that the probability density function (PDF) of the measured residual phase jitter (RPJ) is close to the Gaussian distribution, and the variance of the RPJ increases quadratically with the optical path difference of the CDS. Numerical simulations using stationary white noise confirm these findings, and the experimental results align well with the simulations. Overall, this study provides insights into the noise property of FDML laser-based CDS and evaluates the temporal coherence of swept lasers.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Junsong Peng, Zihan Zhao, Sonia Boscolo, Christophe Finot, Srikanth Sugavanam, Dmitry Churkin, Heping Zeng
Summary: This study observed different types of breather complexes in a mode-locked fiber laser, with intermolecular temporal separation reaching several hundreds of picoseconds, indicating long-range interactions. This opens the possibility of studying the dynamics of many-body systems where breathers are the elementary constituents.
LASER & PHOTONICS REVIEWS
(2021)
Article
Optics
Andreas Dax, Cezary Sydlo, Edwin Divall, Christoph P. Hauri, Martin Huppert, Michael Schaedler, Carlo Vicario, Adrian L. Cavalieri, Bojan Resan, Alexandre Trisorio
Summary: The arrival time jitter and drift of the photocathode drive laser significantly affect the performance of a Free-Electron-Laser, especially for pump-probe experiments with femtosecond time resolution. This paper presents the results of measuring these parameters using a well-designed balanced optical cross correlator, with a focus on the performance of the amplifier.
Article
Optics
Tong Wang, Qun Ren, Kemal Safak, Franz X. Kaertner, Ming Xin
Summary: The new timing detection method based on acousto-optic modulation is immune to dispersion effects, can effectively suppress noise, and achieves timing noise close to the shot noise limit. It has potential applications in ultra-long fiber link stabilization, quantum metrology, weak signal timing control, and more.
Article
Engineering, Electrical & Electronic
Tu T. Nguyen, Tingting Zhang, Elias Giacoumidis, Abdallah A. I. Ali, Mingming Tan, Paul Harper, Liam P. Barry, Andrew D. Ellis
Summary: This article experimentally demonstrates the combined benefit of artificial neural network-based nonlinearity compensation and probabilistic shaping. The proposed scheme shows improved performance for both 64-QAM and 256-QAM probabilistically shaped systems, with additional gains observed in the presence of coupled transceiver and fiber-induced nonlinearities. The experimental results indicate enhanced mutual information up to 0.13 bits/symbol in a fiber link of up to 500 km with the aid of the artificial neural network.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Amol Delmade, Colm Browning, Theo Verolet, Julien Poette, Arman Farhang, Hamza Hallak Elwan, R. David Koilpillai, Guy Aubin, F. Lelarge, Abderrahim Ramdane, Deepa Venkitesh, Liam P. Barry
Summary: This study introduces three different techniques for compensating laser frequency offset and phase noise in an optical heterodyne A-RoF system. The successful transmission of a 1.95 MHz subcarrier spaced OFDM signal demonstrates the effectiveness of these compensation techniques.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Aneesh Sobhanan, Arjun Iyer, Aravind Anthur, Govind P. Agrawal, Liam P. Barry, Deepa Venkitesh
Summary: This paper introduces a general method for optimizing phase quantization using a PSA made using an SOA, and demonstrates two- and four-level phase quantization schemes experimentally. The research shows that using an SOA can achieve pump power levels as low as 1mW at the optimized gain extinction ratio.
Article
Optics
Devika Dass, Marcos Troncoso Costas, Liam P. Barry, Sean O'Duill, Chris G. H. Roeloffzen, Douwe Geuzebroek, Guillermo Carpintero, Robinson Cruzoe Guzman, Colm Browning
Summary: This paper presents a detailed characterization of a novel InP-Si3N4 dual laser module, demonstrating low RIN and wide wavelength tunability. Experimental results show that the module can effectively support PAM-8 transmission and outperform a commercial external cavity laser.
Article
Engineering, Electrical & Electronic
Marcos Troncoso-Costas, Devika Dass, Colm Browning, Francisco J. Diaz-Otero, Chris G. H. Roeloffzen, Liam P. Barry
Summary: Flexible Pulse Amplitude Modulation (FlexPAM) is a technique that uses non-standard PAM formats to increase link capacity. This paper demonstrates FlexPAM as a scalable solution for future data center interconnects and introduces a symbol-to-bit mapping method to minimize the effect of intensity noise. Experimental results show that 20 GBaud transmission was successfully achieved using FlexPAM over 1 km of single-mode fiber without amplification.
IEEE PHOTONICS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Devika Dass, Amol Delmade, Liam Barry, Chris G. H. Roeloffzen, Douwe Geuzebroek, Colm Browning
Summary: A tunable hybrid InP-Si3N4 dual laser module is used to develop a wavelength and frequency flexible optical fronthaul system for high-capacity wireless networks. The module demonstrates the flexible delivery of 5G and WiGig signals, showing excellent performance.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Ahmed Galib Reza, Marcos Troncoso-Costas, Colm Browning, Francisco J. Diaz-Otero, Liam P. Barry
Summary: This work presents the use of a directly modulated laser (DML) in TWDM-PONs, utilizing booster amplification and pre-amplification to improve power budget. The performance of NRZ-OOK, PAM-4, and PAM-8 modulation using a 10G DML is compared. Nonlinear equalizers and machine learning equalizers are applied to mitigate waveform distortions caused by limited bandwidth and laser frequency chirp. The results show that the power budget of PAM-4 54 Gbit/s signals can reach 28 dB for uplink and 35 dB for downlink after 25 km transmission over single-mode fiber.
IEEE PHOTONICS JOURNAL
(2022)
Article
Optics
Haizhong Weng, Adnan Ali Afridi, Jing Li, Michael McDermott, Huilan Tu, Liam P. Barry, Qiaoyin Lu, Weihua Guo, John F. Donegan
Summary: The paper presents a design strategy for obtaining reliable dual modes in the silicon nitride platform with a separation of 10 GHz, which stabilizes soliton formation. The researchers demonstrate the generation of single-solitons spanning 1.5 octaves and the existence of ultra-wide soliton range up to 17 GHz. The proposed scheme also enables the generation of multi-solitons and soliton crystals with enhanced repetition rates and conversion efficiency.
Correction
Optics
Haizhong Weng, Adnan Ali Afridi, Jing Li, Michael McDermott, Huilan Tu, Liam P. Barry, Qiaoyin Lu, Weihua Guo, John F. Donegan
Article
Engineering, Electrical & Electronic
Luis Gonzalez-Guerrero, Robinson Guzman, Muhsin Ali, Alberto Zarzuelo, Jessica Cesar, Devika Dass, Colm Browning, Liam P. Barry, Ilka Visscher, Robert Grootjans, Chris G. H. Roeloffzen, Guillermo Carpintero
Summary: This study demonstrates the application of optical injection locking to a frequency comb of a hybrid InP-Si3N4 dual laser source for high-purity mm-wave generation. The experiment shows that the lasers have potential for continuous locking and achieve high SMSR levels with reduced drift by minimizing bias level applied to the phase actuators.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Haixuan Xu, Amol Delmade, Colm Browning, Ahmad Atieh, Yonglin Yu, Liam P. P. Barry
Summary: This paper presents a practical wavelength reuse bidirectional analog radio-over-fiber (A-RoF) system using a single distributed feedback (DFB) laser. Frequency interleaving and pre-emphasis techniques are employed to improve the spectral efficiency and mitigate interference. The system achieves an asymmetric transmission over 25 km fiber with an aggregate capacity of 20 Gb/s for downlink and 10 Gb/s for uplink using 64-QAM and 16-QAM modulated orthogonal frequency division multiplexing (f-OFDM) signals.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Quantum Science & Technology
Sven Abend, Baptiste Allard, Aidan S. Arnold, Ticijana Ban, Liam Barry, Baptiste Battelier, Ahmad Bawamia, Quentin Beaufils, Simon Bernon, Andrea Bertoldi, Alexis Bonnin, Philippe Bouyer, Alexandre Bresson, Oliver S. Burrow, Benjamin Canuel, Bruno Desruelle, Giannis Drougakis, Rene Forsberg, Naceur Gaaloul, Alexandre Gauguet, Matthias Gersemann, Paul F. Griffin, Hendrik Heine, Victoria A. Henderson, Waldemar Herr, Simon Kanthak, Markus Krutzik, Maike D. Lachmann, Roland Lammegger, Werner Magnes, Gaetano Mileti, Morgan W. Mitchell, Sergio Mottini, Dimitris Papazoglou, Franck Pereira dos Santos, Achim Peters, Ernst Rasel, Erling Riis, Christian Schubert, Stephan Tobias Seidel, Guglielmo M. Tino, Mathias van den Bossche, Wolf von Klitzing, Andreas Wicht, Marcin Witkowski, Nassim Zahzam, Michal Zawada
Summary: Recent developments in quantum technology have led to the creation of a new generation of sensors that can measure inertial quantities with unprecedented sensitivity and accuracy. European laboratories have been at the forefront of this field, developing concepts and tools to operate these quantum sensors in relevant environments. The challenge now is to achieve a sufficiently high technology readiness level to provide off-the-shelf payload for future space missions.
AVS QUANTUM SCIENCE
(2023)
Article
Computer Science, Information Systems
Muyiwa Balogun, Stanislav Derevyanko, Liam Barry
Summary: The nonlinear frequency division multiplexing (NFDM) transmission scheme, known for its robustness against nonlinearity and dispersion, has attracted high interests in optical communications. This study introduces the use of Hermite Gaussian (HG) wave-carriers in a high-capacity dual polarization NFDM (DP-NFDM) transmission system, enhanced by a single parameter equalizer. The system achieves a record-high spectral efficiency of 12 bits/s/Hz.
Article
Computer Science, Information Systems
Sean P. O'duill, Liam P. Barry
Summary: This article reports a technique that utilizes RF quadrature demodulation to measure laser frequency modulation (FM) noise based on a delayed self-heterodyne setup. The measurement is self-referencing and allows for precise characterization of FM noise over a sufficiently long duration. The effectiveness of this technique is demonstrated through measurements on external cavity lasers and a fiber laser, with good agreement between the measured FM noise and the sum of individual FM noise.
Proceedings Paper
Computer Science, Information Systems
Amol Delmade, Colm Browning, Liam P. Barry
2020 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATIONS (ECOC)
(2020)
