Article
Chemistry, Multidisciplinary
Wenna Du, Xianxin Wu, Shuai Zhang, Xinyu Sui, Chuanxiu Jiang, Zhuoya Zhu, Qiuyu Shang, Jianwei Shi, Shuai Yue, Qing Zhang, Jun Zhang, Xinfeng Liu
Summary: Perovskite micro/nanostructures are highly attractive for nanolasers as a gain material. In this study, CsPbBr3 microplatelets with anisotropic properties were obtained and their optical gain was investigated. A polarization-dependent optical gain was observed, with a larger gain along the [002] direction. The highest optical gain value reported so far was achieved along the [002] direction. Furthermore, all optical switching of lasing was realized. These findings provide new insights for the design of novel anisotropic devices based on perovskite micro/nanostructures.
Article
Engineering, Electrical & Electronic
Dariush Jafari, Mohammad Danaie, Pejman Rezaei, Tofiq Nurmohammadi
Summary: In this paper, a novel header extraction scheme based on a semiconductor ring laser is proposed and simulated for proof of principle in all-optical packet switching networks. The simulations and numerical analysis show that this structure can extract headers with more than a 20 dB contrast ratio, making it suitable for integration with other all-optical circuits due to its simplicity and small size.
OPTICAL AND QUANTUM ELECTRONICS
(2021)
Article
Optics
Rujun Liu, Tang Xu, Qiwen Liang, Min Zhao, Shiyu Long
Summary: The proposed method for constructing bistable all-optical switching based on changes in photoinduced-absorption characteristics was experimentally validated and a theoretical model was established to explain the mechanism. The experimental results showed good agreement with the theoretical model, indicating the potential application value of this all-optical switching method.
Article
Engineering, Electrical & Electronic
Ji-Hyun Park, Su-Yeon Kim, Sung-Han Kim, Shinwook Yu, Sang-Bae Kim
Summary: The study reveals that the lasing spectra of VCSELs are primarily determined by the DC bias current, with little impact from bitrates and modulation amplitudes. When the off-state current is much higher than the threshold, transverse modes respond to the modulation current in a synchronized manner.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Yaya Doumbia, Delphine Wolfersberger, Krassimir Panajotov, Marc Sciamanna
Summary: In this study, a new approach of broadband comb generation based on the polarization mode competition in single-mode VCSELs is experimentally demonstrated. The results show that single or dual polarization combs with controllable properties can be induced by polarization mode competition under certain injection parameters. The performance of the dual polarization combs depends on the injection current and injected comb spacing.
Article
Optics
Vartika Rao, Sanjoy Mandal
Summary: This paper presents a simple design of optically pumped counters using optical J-K flip flop based on Silicon waveguide OMRR, leveraging the non-linearity characteristic of OMRR. The counter circuit is achieved using a delay line signal process approach. The circuit's performance is assessed through exploration of Z-domain model, evaluating various performance parameters during simulation.
Article
Engineering, Electrical & Electronic
Nestor Lozano-Crisostomo, Julio C. Garcia-Melgarejo, Miguel A. Gonzalez-Galicia, Cesar A. Baez-Lopez, Juan C. Hurtado-Carrazco, J. Javier Sanchez-Mondragon
Summary: The article presents a comprehensive theory for describing and controlling the nonlinear polarization conversion of circularly polarized light in birefringent optical fibers. A nonlinear model is provided to accurately obtain input powers and tune the most common continuous-wave polarization states at the output. Analysis of the polarization instability of the output signals is also conducted, with the theory opening up new perspectives on all-optical polarization control with birefringent optical fibers.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Sami S. Alharthi
Summary: We propose and demonstrate a scheme for generating photonic microwave signals with a very wide tunability range using spin-VCSELs. By adjusting the frequency of the injected light, the generated microwave frequencies can be tuned. The system utilizes polarization switching phenomena of spin-VCSELs to achieve a broader range of microwave frequencies.
RESULTS IN PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Tong Zhang, Zhiwei Jia, Anbang Wang, Yanhua Hong, Longsheng Wang, Yuanyuan Guo, Yuncai Wang
Summary: In a vertical-cavity surface-emitting laser with polarization-preserved external-cavity optical feedback, two new dynamic-state switching phenomena have been experimentally observed. These switching phenomena provide new insights into the understanding of laser nonlinear dynamics.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Biqiang Jiang, Yueguo Hou, Hongyang Wang, Xuetao Gan, Ailun Li, Zhen Hao, Kaiming Zhou, Lin Zhang, Jianlin Zhao
Summary: Integration of graphene with optical fibers enables fast response all-optical switching by modulating the transmission spectrum of a tilted fiber Bragg grating (TFBG) through pump power adjustment, promising a dynamic response of around 1 microsecond and an extinction ratio exceeding 13 dB. This compact device has the potential to be integrated into all-fiber systems to extend the functions of all-optical signal processing.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Nobuhide Yokota, Kazuhiro Ikeda, Hiroshi Yasaka
Summary: This study proposes and investigates the use of birefringent VCSELs for analog RoF systems, demonstrating the generation of 24GHz carrier and heterodyne detection of square-wave signals. The findings show the potential of applying spin-injected birefringent VCSELs for ultra-high-frequency modulation in analog RoF systems.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2021)
Article
Computer Science, Information Systems
Javid Ahmad Ganie, Kushmanda Saurav
Summary: This paper presents a low profile, 1-bit phase quantized, polarization rotating, and switchable beam transmitarray for millimeter-wave MIMO applications. The transmitarray is designed based on polarization rotating elements and exhibits wideband characteristics. It can be used for beamforming in future 5G millimeter wave communications.
Article
Engineering, Electrical & Electronic
Apostolos Tsakyridis, Nikos Terzenidis, George Giamougiannis, Miltiadis Moralis-Pegios, Konstantinos Vyrsokinos, Nikos Pleros
Summary: The paper discusses the challenges and limitations of current electrical DataCenter switches in scaling beyond the 25.6 Tb/s capacity-era and the perspectives and challenges of migrating to Optical Packet Switch (OPS) technologies. The feasibility and performance of OPS schemes are demonstrated through experimental results, showcasing the potential of OPS in overcoming electronic bottlenecks and achieving high switch capacities.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Chemistry, Multidisciplinary
Maria Pilar Fernandez-Gallego, Doroteo T. Toledano
Summary: Client conversations in contact centers are valuable sources of information that can be effectively extracted and analyzed using Automatic Speech Recognition (ASR). However, the use of Voice-over-IP (VoIP) in these systems often leads to packet losses and speech signal interruptions, negatively impacting ASR performance. This article extensively studies the importance of these effects and explores the effectiveness of data augmentation and Packet Loss Concealment (PLC) techniques in improving ASR performance on signals affected by packet losses.
APPLIED SCIENCES-BASEL
(2022)
Article
Optics
Ambaresh Sahoo, Dipti Kanika Mahato, A. Govindarajan, Amarendra K. Sarma
Summary: We investigate switching dynamics in a PT-symmetric fiber coupler composed of a saturable nonlinear material as the core. Our findings show richer soliton switching dynamics than conventional counterparts, which may lead to ultrafast and efficient all-optical switching dynamics. Furthermore, we provide a suitable range of system and pulse parameters for practical realization of the coupler in all-optical switching devices and photonic circuits. The developed variational approach excellently predicts the numerical findings.