1
|
Yunan H, Jiang C, Xiong S, Liu Z. Filter cable design with defected conductor transmission structures. COMMUNICATIONS ENGINEERING 2024; 3:111. [PMID: 39152246 PMCID: PMC11329786 DOI: 10.1038/s44172-024-00262-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 08/05/2024] [Indexed: 08/19/2024]
Abstract
Electrical cables, as the industry's blood vessels and nervous system, require evolving distributed filtering for complex electromagnetic environment adaptability. This article introduces a filter cable design featuring an insulated cylinder coated with a defected conductor transmission structure (DCTS). The DCTS, with a well-designed etched pattern, functions as a boundary condition for transmitting specific frequency electromagnetic waves, similar to a lumped filter circuit. To validate this method, a low-pass filter cable is proposed with six-slot-ring defected structures, utilizing polytetrafluoroethylene as the inner dielectric, encased within a flexible printed circuit board (FPCB)-manufactured DCTS. The proposed cable, with precise dimensions (2.4 mm diameter, 340 mm length), demonstrates minimal insertion loss ( < 0.38 dB below 6 GHz) in the passband and rejection exceeding 23 dB at 7.7-25 GHz in the stopband. Further enhancements achieve attenuation exceeding 50 dB in the stopband (7.1 GHz to 20 GHz). Compared to traditional cables, this filter cable addresses electromagnetic compatibility (EMC) by cutting off the interference coupling path.
Collapse
Affiliation(s)
- Han Yunan
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China.
| | - Cuilian Jiang
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Shuangqing Xiong
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Zhaohan Liu
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, China.
| |
Collapse
|
2
|
Crespo-Ballesteros M, Sumetsky M. Ultra-precise, sub-picometer tunable free spectral range in a parabolic microresonator induced by optical fiber bending. OPTICS LETTERS 2024; 49:4354-4357. [PMID: 39090932 DOI: 10.1364/ol.529557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 07/09/2024] [Indexed: 08/04/2024]
Abstract
Surface nanoscale axial photonic (SNAP) microresonators are fabricated on silica optical fibers, leveraging silica's outstanding material and mechanical properties. These properties allow for precise control over the microresonators' dimension, shape, and mode structure, a key feature for reconfigurable photonic circuits. Such circuits find applications in high-speed communications, optical computing, and optical frequency combs (OFCs). However, consistently producing SNAP microresonators with equally spaced eigenmodes has remained challenging. In this study, we introduce a method to induce a SNAP microresonator with a parabolic profile. We accomplish this by bending a silica optical fiber in a controlled manner using two linear stages. This approach achieves a uniform free spectral range (FSR) as narrow as 1 pm across more than 45 modes. We further demonstrate that the FSR of the SNAP microresonator can be continuously adjusted over a range nearly as wide as one FSR itself, specifically from 1.09 to 1.72 pm, with a precision of ±0.01 pm and high repeatability. Given its compact size and tuning capability, this SNAP microresonator is highly promising for various applications, including the generation of tunable low-repetition-rate OFC and delay lines.
Collapse
|
3
|
Han Y, Xiong S, Cheng C, Liu Z. Design of filtering cable with defected conductor layer. Sci Rep 2024; 14:5227. [PMID: 38433279 PMCID: PMC10909839 DOI: 10.1038/s41598-024-55736-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 02/27/2024] [Indexed: 03/05/2024] Open
Abstract
Electrical cables, often referred to as 'blood vessels' and 'nerves' of the industry, play a vital role in the connection of electrical devices. However, traditional cables that lack distributed filtering functions are usually the primary coupling path for electromagnetic compatibility (EMC) problems. An innovative design for a filtering cable, which incorporates insulated electrical wires coated with a specific defected conductor layer (DCL), enables it to achieve distributed filtering advantages along its axis. Microwave network analysis is employed to build the two-port network model of filtering cable, which efficiently analyzes the cascading characteristics of periodic or aperiodic filtering cables. To validate, the flexible printed circuit board (FPCB) with sawtooth dumbbell-shaped DCL and mounted by capacitors is wrapped around the stripped section of the coaxial cable to manufacture a multi-stopband filtering cable. Simulated and measured results demonstrate that the proposed filtering cable can be effectively suppressed in the stopband, which can be adjusted by changing the values of capacitors.
Collapse
Affiliation(s)
- Yunan Han
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Shuangqing Xiong
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Chunyue Cheng
- Beijing Institute of Radio Metrology and Measurement, Beijing, 100854, China
| | - Zhaohan Liu
- Department of the College of Information Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China.
| |
Collapse
|
4
|
Negrini S, Ceppe JB, Conforti M, Perego AM, Kudlinski A, Mussot A. Coexistence of gain-through-filtering and parametric instability in a fiber ring cavity. OPTICS EXPRESS 2023; 31:37011-37018. [PMID: 38017838 DOI: 10.1364/oe.498572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 09/02/2023] [Indexed: 11/30/2023]
Abstract
We experimentally and numerically investigate the dynamics of a fiber ring cavity in which two different instability can be excited: gain-through-filtering and parametric instability. We demonstrate that they can be triggered individually or collectively depending on the two main control parameters offered by the cavity, namely the pump power and the cavity detuning. The experimental observations are in good agreement with numerical simulations.
Collapse
|
5
|
Liu M, Dang Y, Huang H, Lu Z, Mei S, Cai Y, Zhou W, Zhao W. Vector solitonic pulses excitation in microresonators via free carrier effects. OPTICS EXPRESS 2023; 31:32172-32187. [PMID: 37859026 DOI: 10.1364/oe.498671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/02/2023] [Indexed: 10/21/2023]
Abstract
We numerically investigate the excitation of vector solitonic pulse with orthogonally polarized components via free-carrier effects in microresonators with normal group velocity dispersion (GVD). The dynamics of single, dual and oscillated vector pulses are unveiled under turn-key excitation with a single frequency-fixed CW laser source. Parameter spaces associated with detuning, polarization angle, interval between the pumped orthogonal resonances and pump amplitude have been revealed. Different vector pulse states can also be observed exploiting the traditional pump scanning scheme. Simultaneous and independent excitation regimes are identified due to varying interval of the orthogonal pump modes. The nonlinear coupling between two modes contributes to the distortion of the vector pulses' profile. The free-carrier effects and the pump polarization angle provide additional degrees of freedom for efficiently controlling the properties of the vector solitonic microcombs. Moreover, the crucial thermal dynamics in microcavities is discussed and weak thermal effects are found to be favorable for delayed vector pulse formation. These findings reveal complex excitation mechanism of solitonic structures and could provide novel routes for microcomb generation.
Collapse
|
6
|
Zhang B, Chen N, Lu X, Chen Y, Zhang X, Xu J. Dissipative Kerr single soliton generation with extremely high probability via spectral mode depletion. FRONTIERS OF OPTOELECTRONICS 2022; 15:48. [PMID: 36637629 PMCID: PMC9756270 DOI: 10.1007/s12200-022-00047-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/15/2022] [Indexed: 06/17/2023]
Abstract
Optical Kerr solitons generation based on microresonators is essential in nonlinear optics. Among various soliton generation processes, the single soliton generation plays a pivotal role since it ensures rigorous mode-locking on each comb line whose interval equals the free spectral range (FSR) of the microresonator. Current studies show that single soliton generation is challenging due to cavity instability. Here, we propose a new method to greatly improve single soliton generation probalility in the anomalous group velocity dispersion (GVD) regime in a micro-ring resonator based on silicon nitride. The improvement is realized by introducing mode depletion through an integrated coupled filter. It is convenient to introduce controllable single mode depletion in a micro-ring resonator by adjusting the response function of a coupled filter. We show that spectral mode depletion (SMD) can significantly boost the single soliton generation probability. The effect of SMD on the dynamics of optical Kerr solitons generation are also discussed. The proposed method offers a straightforward and simple way to facilitate robust single soliton generation, and will have an impact on the research development in optical Kerr soliton generation and on-chip optical frequency mode manipulation.
Collapse
Affiliation(s)
- Boqing Zhang
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Nuo Chen
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Xinda Lu
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yuntian Chen
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Xinliang Zhang
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jing Xu
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.
| |
Collapse
|
7
|
Liu M, Dang Y, Huang H, Lu Z, Wang Y, Cai Y, Zhao W. Loss modulation assisted solitonic pulse excitation in Kerr resonators with normal group velocity dispersion. OPTICS EXPRESS 2022; 30:30176-30186. [PMID: 36242126 DOI: 10.1364/oe.464145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 07/18/2022] [Indexed: 06/16/2023]
Abstract
We demonstrate an emergent solitonic pulse generation approach exploiting the externally introduced or intrinsic loss fluctuation effects. Single or multiple pulses are accessible via self-evolution of the system in the red, blue detuning regime or even on resonance with loss perturbation. The potential well caused by the loss profile not only traps the generated pulses, but also helps to suppress the drift regarding high-order dispersion. Breathing dynamics is also observed with high driving force, which can be transferred to stable state by backward tuning the pump detuning. We further investigate the intrinsic free carrier absorption, recognized as unfavored effect traditionally, could be an effective factor for pulse excitation through the time-variant loss fluctuation in normal dispersion microresonators. Pulse excitation dynamics associated with physical parameters are also discussed. These findings could establish a feasible path for stable localized structures and Kerr microcombs generation in potential platforms.
Collapse
|
8
|
Dong X, Spiess C, Bucklew VG, Renninger WH. Chirped-pulsed Kerr solitons in the Lugiato-Lefever equation with spectral filtering. PHYSICAL REVIEW RESEARCH 2021; 3:033252. [PMID: 35434640 PMCID: PMC9012338 DOI: 10.1103/physrevresearch.3.033252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Optical Kerr resonators support a variety of stable nonlinear phenomena in a simple and compact design. The generation of ultrashort pulses and frequency combs has been shown to benefit several applications, including spectroscopy and telecommunications. The most common anomalous dispersion Kerr resonators can be accurately described by a well-studied mean-field Lugiato-Lefever equation (LLE). Recently observed highly chirped pulses in normal dispersion resonators with a spectral filter, however, cannot. Here we examine the LLE in the normal dispersion regime modified with a Gaussian spectral filter (LLE-F). In addition to solutions associated with the LLE, we find stable highly chirped pulses. Solutions are strongly dependent on the filter bandwidth. Because of the large changes per round trip, the validity of the LLE-F fails over a large range of experimentally relevant parameters. While the mean-field approach leads to accurate predictions with respect to the nonlinearity coefficient and the dispersion, the dependence of drive power on loss deviates significantly from an experimentally accurate model, which leads to opportunities for Kerr resonators including frequency comb generation from low-Q-factor cavities.
Collapse
Affiliation(s)
- Xue Dong
- Institute of optics, University of Rochester, Rochester, New York 14627
| | | | - Victor G. Bucklew
- Institute of optics, University of Rochester, Rochester, New York 14627
| | | |
Collapse
|
9
|
Radhakrishnan S, Colaux H, Chandran CV, Dom D, Verheyden L, Taulelle F, Martens J, Breynaert E. Trace Level Detection and Quantification of Crystalline Silica in an Amorphous Silica Matrix with Natural Abundance 29Si NMR. Anal Chem 2020; 92:13004-13009. [PMID: 32830954 DOI: 10.1021/acs.analchem.0c01756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A protocol for the detection of trace amounts of quartz in amorphous silica gels by NMR spectroscopy was developed and tested on commercially available samples. Using natural abundance 29Si MAS NMR spectroscopy with CPMG acquisition and standard addition of crystalline quartz, quantitative detection of quartz concentrations down to 0.1% wt. was achieved. CPMG permitted to suppress the amorphous silica-derived signal, benefitting from the extremely long T2 relaxation time of quartz in 29Si and hence dramatically increasing the sensitivity. Dedicated post-processing exploiting the known CPMG spikelet frequencies allowed to probe the near-absence of quartz in commercial, 100% silica samples, enabling assessment of conformity of unknown samples to EU legislation (REACH).
Collapse
Affiliation(s)
- Sambhu Radhakrishnan
- NMRCoRe, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium.,Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - Henri Colaux
- Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - C Vinod Chandran
- NMRCoRe, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium.,Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - Dirk Dom
- NMRCoRe, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium.,Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - Loes Verheyden
- Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - Francis Taulelle
- NMRCoRe, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium.,Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - Johan Martens
- NMRCoRe, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium.,Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| | - Eric Breynaert
- NMRCoRe, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium.,Center for Surface Chemistry and Catalysis - Characterisation and Application Team (COK-kat), Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, box 2461, 3001 Leuven, Belgium
| |
Collapse
|