Article
Engineering, Electrical & Electronic
Guangwei Cong, Yuriko Maegami, Morifumi Ohno, Koji Yamada
Summary: In this study, non-TW carrier-depletion MZMs with densely meandered phase shifters were demonstrated to achieve better compromises and high bandwidth, improving the integration density of modulators in wavelength-division multiplexing transceivers. The experiment reached up to 28.1 Gbps NRZ eye diagrams and 26 GHz electro-optic bandwidth. Proposed lumped circuit models explained the data, indicating impedance mismatching and LC resonance play key roles in determining experimental bandwidth. Further driving configurations with better impedance matching were proposed to enhance bandwidth.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Optics
Amr O. Ghoname, Ahmed E. Hassanien, Edmond Chow, Lynford L. Goddard, Songbin Gong
Summary: This work demonstrates a monolithic integrated Michelson interferometer modulator on thin-film lithium niobate (LN), achieving linearized performance by modulating Bragg grating reflectors. The modulator utilizes spiral-shaped waveguide Bragg gratings on LN with extensive reflectors, realized by top and bottom electrodes. The compact design fits a 3 mm long grating in an 80 μm x 80 μm area, offering a broad operating bandwidth up to 18 GHz.
Article
Engineering, Electrical & Electronic
Yosuke Hinakura, Daichi Akiyama, Hiroyuki Ito, Toshihiko Baba
Summary: This study introduces a silicon photonic crystal waveguide slow light Mach-Zehnder modulator, which enhances modulation efficiency and maintains a wide working spectrum. By matching the phase using meanderline electrodes, the cutoff frequency is significantly improved, demonstrating high-speed modulation capabilities.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
B. Maragathaeswari, Hudhaifah Ibn Saleem, Viswas Sadasivan
Summary: A novel shape optimization procedure is proposed to achieve higher phase change while maintaining high transmission in phase modulators. The procedure is implemented as a shape optimization tool and tested on subwavelength grating-based Si carrier depletion and injection modulators. The results demonstrate that the optimized structures can optimize both transmission and phase modulation of carrier injection and depletion modulators, enabling the creation of compact modulators with low drive voltages.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Chen Shang, Matthew R. Begley, Daniel S. Gianola, John E. Bowers
Summary: This study combines models of dislocation motion and thin film channel cracking to solve the cracking issue caused by threading dislocation density in silicon photonic integrated circuits. The proposed solutions include increasing optical confinement and reducing total layer thickness.
Article
Engineering, Electrical & Electronic
Dun Mao, Chen Cheng, Feifan Wang, Yahui Xiao, Tiantian Li, Lorry Chang, Anishkumar Soman, Thomas Kananen, Xian Zhang, Michael Krainak, Po Dong, Tingyi Gu
Summary: Graphene's atomic layer thin geometry and semi-metallic band diagram can enhance the performance of integrated photonic devices. By utilizing its semiconductor-like behavior and low loss properties, graphene can function as an active layer for electro-optic modulation with ultrafast speeds and energy efficiency. Hybrid device architectures, such as directly contacted graphene-silicon heterojunctions and graphene integrated lithium niobite modulators, demonstrate potential for high-speed modulation and improved coupling coefficient between optical and electric fields.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Souvaraj De, Ranjan Das, Ravendra K. Varshney, Thomas Schneider
Summary: A comprehensive analysis was conducted on the thermal crosstalk issue in silicon photonic circuits, using metal and doped silicon heaters for different waveguide configurations. By performing full-wave thermal and optical simulations, the study proposed solutions to reduce phase crosstalk and improve thermal tuning efficiency, demonstrating superior performance in thermal crosstalk over existing designs for compact silicon photonic circuits operating at high temperatures.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Weiwei Zhang, Kapil Debnath, Bigeng Chen, Ke Li, Shenghao Liu, Martin Ebert, Jamie Dean Reynolds, Ali Z. Khokhar, Callum Littlejohns, James Byers, Muhammad K. Husain, Frederic Y. Gardes, Shinichi Saito, David J. Thomson
Summary: This paper analyzed and optimized the structure of horizontal Silicon insulator Silicon capacitor (H-SISCAP) phase shifters, which can achieve high bandwidth modulators for optical transmitters with data rates up to 60 Gbit/s.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Hanke Feng, Ke Zhang, Wenzhao Sun, Yangming Ren, Yiwen Zhang, Wenfu Zhang, Cheng Wang
Summary: This research demonstrates a highly linear lithium niobate (LN) modulator with an ultra-high spurious-free dynamic range (SFDR) using a ring-assisted Mach-Zehnder interferometer configuration. The modulation does not require active feedback controls to suppress third-order intermodulation distortions (IMD3), resulting in a significant improvement over previous results in the thin-film LN platform.
PHOTONICS RESEARCH
(2022)
Article
Optics
Wei Luo, Liying Lin, Jie Huang, Yu Han, Kei May Lau
Summary: This study demonstrates the direct epitaxy of InP quantum dot lasers on silicon, achieving continuous-wave lasing at room temperature. Micro-disk lasers on silicon have a low threshold similar to those on native GaAs substrates, confirming the performance of QD lasers on silicon.
Article
Engineering, Electrical & Electronic
Brian Murray, Cleitus Antony, Giuseppe Talli, Paul D. Townsend
Summary: This study demonstrates the use of electrical precompensation for high-speed operation of lumped MZMs through experiment and simulation. A precise equivalent circuit model is fitted to S11 measurements to analyze design trade-offs in terms of system performance, energy consumption, and drive voltage requirements. The results show that careful selection of source resistance with respect to electrode and packaging inductance is crucial for high-speed modulation. Increasing the electrode inductance is shown to be beneficial as it allows optimum performance with a higher source impedance. Furthermore, combining precompensation with a slight inductive peaking and optimized source resistance is demonstrated to reduce drive voltage requirements and energy dissipation in the circuit.
IEEE PHOTONICS JOURNAL
(2022)
Article
Optics
Yuhan Yao, Yuhe Zhao, Yanxian Wei, Feng Zhou, Daigao Chen, Yuguang Zhang, Xi Xiao, Ming Li, Jianji Dong, Shaohua Yu, Xinliang Zhang
Summary: This article presents a highly integrated dual-modality microwave frequency identification system on a single chip, which can identify different types of microwave signals and discriminate instantaneous frequency variation among the frequency-modulated signals. This technology can meet the requirements of reduction in size, weight, and power for future advanced microwave photonic processors.
LASER & PHOTONICS REVIEWS
(2022)
Review
Nanoscience & Nanotechnology
Iman Taghavi, Maryam Moridsadat, Alexander Tofini, Shaheer Raza, Nicolas A. F. Jaeger, Lukas Chrostowski, Bhavin J. Shastri, Sudip Shekhar
Summary: Optical modulators are crucial for various applications, but current Si modulator technologies have limitations. Si-organic-hybrid (SOH) modulators, with additional materials, offer larger modulation bandwidth and smaller drive voltage or footprint. However, SOH modulators also face challenges related to aging and temperature.
Article
Chemistry, Multidisciplinary
Zhenyu Wang, Cheol-Yeon Cheon, Mukesh Tripathi, Guilherme Migliato Marega, Yanfei Zhao, Hyun Goo Ji, Michal Macha, Aleksandra Radenovic, Andras Kis
Summary: In this study, epitaxial chemical vapor deposition growth of 2D NbS2 crystals on a sapphire substrate was demonstrated, with controlled thickness and phase transition. The high-quality superconducting properties of the NbS2 crystals were confirmed through Raman spectroscopy, STEM, and electrical transport measurements, making them suitable for next-generation TMDC-based electrical devices.
Article
Engineering, Electrical & Electronic
Laurens Breyne, Joris Lambrecht, Michiel Verplaetse, Xin Yin, Gunther Roelkens, Peter Ossieur, Johan Bauwelinck
Summary: A novel method is introduced to embed finite-impulse-response filters in slow-wave Mach-Zehnder modulators, allowing the adjustment of the electro-optic frequency response to designer's needs. The position of delay lines and crossings, along with the length of delay lines in the modulator, determine the final response. Experimental validation on a silicon photonic modulator and C-band transmission experiments demonstrate the effectiveness of this technique.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Alireza Tabatabaei Mashayekh, Thomas Klos, Douwe Geuzebroek, Edwin Klein, Theo Veenstra, Martin Buscher, Florian Merget, Patrick Leisching, Jeremy Witzens
Summary: A multi-color laser engine with silicon nitride photonic integrated circuit technology has been implemented, combining four fluorophore excitation wavelengths for imaging. This technology reduces the optics volume significantly and enables light multiplexing and fiber switching. Spectrally resolved performance of the developed devices has been characterized.
Article
Engineering, Electrical & Electronic
Jovana Nojic, Alireza Tabatabaei-Mashayekh, Talha Rahman, Alvaro Moscoso-Martir, Florian Merget, Xu Sun, Jeremy Witzens
Summary: An analytical model is introduced to describe the statistical and spectral properties of laser phase noise induced intensity noise in ring-resonator-based modulation. Experimental validation confirms the model's effectiveness, showing high-speed data transmission performance with SSB-OFDM over single-mode fiber.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Optics
Andrea Zazzi, Juliana Mueller, Ibrahim Ghannam, Moritz Battermann, Gayatri Vasudevan Rajeswari, Maxim Weizel, J. Christoph Scheytt, Jeremy Witzens
Summary: This study presents the design and experimental characterization of a silicon nitride pulse interleaver based on coupled resonator optical waveguide filters. The application of this device in time-interleaved photonically-assisted ADCs is analyzed, and the impact of signal distortion and noise sources on the converter is investigated. Suitable equalization techniques at the digital signal processing level are evaluated, and the use of a powerful equalization filter in the DSP domain is shown to significantly improve the digitized signal SNR. The expected performance of the device with compact and off-the-shelf single-section semiconductor mode locked lasers is discussed.
Article
Engineering, Electrical & Electronic
Dengyang Fang, Andrea Zazzi, Juliana Mueller, Daniel Drayss, Christoph Fuellner, Pablo Marin-Palomo, Alireza Tabatabaei Mashayekh, Arka Dipta Das, Maxim Weizel, Sergiy Gudyriev, Wolfgang Freude, Sebastian Randel, J. Christoph Scheytt, Jeremy Witzens, Christian Koos
Summary: We present an optical arbitrary waveform measurement (OAWM) system that uses a bank of silicon photonic (SiP) frequency-tunable coupled-resonator optical waveguide (CROW) filters for continuous spectral slicing of broadband optical signals. By using a frequency comb as a multi-wavelength local oscillator (LO) and digital signal processing (DSP), the spectral slices are coherently detected and stitched together. Our proof-of-concept experiment demonstrates the feasibility of the scheme.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Alvaro Moscoso-Martir, Jonas Koch, Olaf Schulz, Juliana Mueller, Ali Tabatabaei Mashayekh, Arka D. Das, Florian Merget, Stephan Pachnicke, Jeremy Witzens
Summary: We present a silicon photonic transmitter for soliton-based communications that allows interleaving of QPSK and APSK modulated soliton pulses overlapping in both time and frequency domains. By employing the nonlinear Fourier transform, we determine suitable soliton launch conditions and facilitate nonlinear equalization at the receiver. We achieve a spectral efficiency of 0.5 b/s/Hz per polarization over a transmission distance of 5400 km, which is a record for soliton transmission over such long distances. Experimental comparisons of linear and nonlinear minimum mean square error and artificial neural network-based equalizers demonstrate the effectiveness of artificial neural networks in this system.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Cristina Rimoldi, Lorenzo Luigi Columbo, Jock Bovington, Sebastian Romero-Garcia, Mariangela Gioannini
Summary: This study addresses the stability of a tunable hybrid laser consisting of a III-V Reflective Semiconductor Optical Amplifier (RSOA) and a Silicon Photonic (SiPh) dispersive mirror. The researchers developed a model based on time-delayed algebraic differential equations to analyze the laser's stability and the impact of the mirror's bandwidth on damping of relaxation oscillations and photon-photon resonance. The study also examined the laser's tolerance to external optical feedback and identified a mirror design with ultra-high stability.
Article
Optics
Marco Novarese, Sebastian Romero Garcia, Stefania Cucco, Don Adams, Jock Bovington, Mariangela Gioannini
Summary: A detailed description of the non-linear effects in silicon is necessary for designing ring resonators on the silicon platform. This study presents a new approach for modeling the non-linear effects in silicon-based ring resonators and validates the model through experimental measurements.
Article
Optics
Manuel Ackermann, Florian Merget, Jeremy Witzens
Summary: Silicon photonics ring resonators play a crucial role in wavelength-division-multiplexed communication networks. However, bending losses become unacceptable when the circumference is reduced below a few micrometers. This paper proposes the use of a sub-wavelength tunneling barrier at the critical radius to suppress these losses without significantly increasing the resonator's resistance.
Article
Optics
Prachi Agrawal, Farshid Ashtiani, Florian Merget, Firooz Aflatouni, Jeremy Witzens
Summary: Optical phased arrays are a powerful tool for compact beam scanners, but tuning large-scale 2D arrays is challenging. This study combines 1D beam steering and nonlinear mixing using an optically addressable liquid crystal cell, with optimization of the addressable angular ranges and nonlinear transformation strength.
Article
Engineering, Electrical & Electronic
Cristina Rimoldi, Lorenzo L. Columbo, Jock Bovington, Sebastian Romero-Garcia, Mariangela Gioannini
Summary: This article reports on the operation of external cavity III-V/SiN hybrid lasers in regimes of ultra-damped relaxation oscillations or CW unstable dynamical regimes (self-pulsing or approaching turbulence), which result from mirror dispersion, non-zero linewidth enhancement factor, and four-wave mixing in the gain medium. The impact of dispersive mirror bandwidth and different mirror effective lengths on the laser tolerance to external optical feedback is also discussed.
IEEE PHOTONICS JOURNAL
(2022)
Article
Materials Science, Multidisciplinary
M. Frauenrath, O. Concepcion, N. Gauthier, E. Nolot, D. Buca, J. -M. Hartmann
Summary: In this study, the in situ Boron and Phosphorous doping of SiGeSn was investigated to improve the performances of GeSn based devices. The doping resulted in smoother surfaces and higher carrier concentrations, which are beneficial for (Si)GeSn based devices and Group-IV based devices with low thermal budget constraints.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2023)
Proceedings Paper
Computer Science, Information Systems
F. Merget, M. Ackermann, B. Shen, G. D. Saunders, S. Haag, M. Wolz, J. Witzens
Summary: The glass-molded micro-optical interposers for single mode fiber-to-PIC coupling, fabricated at the wafer scale, result in less than 1 dB excess insertion losses. They offer a narrow package footprint and can potentially support polarization management, isolation, and wavelength multiplexing.
2021 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION (ECOC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Dengyang Fang, Andrea Zazzi, Juliana Mueller, Daniel Drayss, Christoph Fuellner, Pablo Marin-Palomo, Ali Tabatabaei Mashayekh, Arka Dipta Das, Maxim Weizel, Sergiy Gudyriev, Wolfgang Freude, Sebastian Randel, Christoph Scheytt, Jeremy Witzens, Christian Koos
Summary: This study demonstrates optical arbitrary waveform measurement using a silicon photonic spectral slicer. By leveraging maximal-ratio combining, the researchers successfully reconstructed 100-GBd 64QAM signals with high quality.
2021 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
J. Koch, A. Moscoso-Martir, J. Mueller, A. Tabatabaei Mashayekh, A. D. Das, F. Merget, S. Pachnicke, J. Witzens
Summary: The silicon-photonics transmitter experimentally demonstrated the modulation and optical merging of solitons with different frequency and time spacing based on the nonlinear Fourier-transform, offloading electronics. Two soliton channels successfully transmitted up to 5000 km.
2021 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2021)
