Article
Engineering, Electrical & Electronic
Yuting Bai, Yinping Miao, Hongmin Zhang, Chengwei Fei, Bin Li, Kailiang Zhang
Summary: A fiber-optic sensor based on microfiber coupler is proposed for dual parameter detection of acetaminophen and temperature. The sensor showed detection sensitivities for acetaminophen concentration and temperature, indicating its potential application in pharmaceutical quality control and hospital wastewater treatment.
IEEE SENSORS JOURNAL
(2021)
Article
Engineering, Electrical & Electronic
Luqing Shao, Yingxin Xu, Hao Wu, Wei Fang, Limin Tong
Summary: A single-mode fiber coupler with variable coupling ratio based on microfibers was demonstrated in this study, showing compact size and wide tuning range. By adjusting the twisting angle between the microfibers, the coupling ratio can be varied from 3.15% to 98.5%. Numerical simulations and experimental results were in good agreement, and the effects of diameter discrepancy and mode polarization were studied.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2021)
Article
Optics
Dora Juan Juan Hu, Linbo Liu, Hui Dong, Hailiang Zhang
Summary: In this paper, an optical fiber-based broadband mode coupler for multimode optical coherence tomography (OCT) in the O-band is proposed. The device uses a tapered few-mode fiber (FMF) to achieve efficient mode coupling between the higher-order modes of the FMF and the fundamental mode of a single-mode fiber (SMF). Key design parameters such as the tapering ratio, core separation, coupler length, and coupling ratio in the O-band are thoroughly studied. The proposed fiber device allows for better signal collection and improved penetration depth in deep tissue imaging for multimode OCT.
Article
Optics
Linghua Wang, Fengyang Han, Huaixi Chen, Jiwei Huang, Yazhen Zhang, Xinbin Zhang, Xinkai Feng, Rongshan Wei, Shaohao Wang, Minmin Zhu
Summary: This paper proposes a CMOS-compatible, broadband, and polarization-independent edge coupler for efficient chip coupling with standard single-mode fiber. By using a three-layer silicon nitride waveguide array with the same structures in the top oxide cladding of the chip, high coupling efficiency and simplified mode transformation structure can be achieved. The structure has the potential to reduce the packaging cost of silicon photonic chips and can be used for on-chip three-dimensional photonic integrations or fiber-to-chip, chip-to-chip optical interconnections.
Article
Engineering, Electrical & Electronic
Junjie Weng, Yang Yu, Jianfa Zhang, Dongying Wang, Zhechun Lu, Zhencheng Wang, Jianqiao Liang, Shumao Zhang, Xiangcheng Li, Yang Lu, Zhou Meng, Junbo Yang, Zhenrong Zhang
Summary: In this paper, a biomimetic optical skin (BOS) based on optical microfiber coupler neuron (OMCN) is proposed, which realizes multimodal tactile perception for the first time. BOS can sensitively detect temperature, contact force, vibration, and recognize the hardness and roughness of objects through human-like tactile sensing. Furthermore, the excellent repeatability and stability of BOS are investigated, laying the foundation for practical applications.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Mohammad Hassan Maghsoudian, Hamidreza Karimi-Alavijeh
Summary: This study presents a fast single-step process for fabricating microfiber long period gratings (MLPGs) using the arc-discharge fiber heating and pulling technique. The developed one-step technique enables the fabrication of MLPGs with low insertion loss, high resonance dip, and simple configuration in less than 100s. The fabricated MLPGs exhibit high resonance dip (> 27 dB), low transmission loss (<= 1.2 +/- 0.2 dB), narrow FWHM (< 20 nm), and high repeatability. The results of this study are important for the realization of miniature fiber optics elements and sensors.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Bruna Paredes, Zakriya Mohammed, Juan Esteban Villegas, Mahmoud Rasras
Summary: We designed and demonstrated an ultra-compact and ultra-broadband two-mode de-multiplexer based on a subwavelength grating (SWG) asymmetrical coupler (ADC) on a silicon-on-insulator (SOI) platform. The device consists of a cascaded strip waveguide tapered to a multimode segment and a SWG-based single-mode waveguide. The MDM link operates over a wide wavelength range, covering the entire S-, C-, and L-bands, achieving low insertion loss and crosstalk.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Jiajie Wen, Xiangyu Yan, Xu Gao, Kaiwei Li, Jiajia Wang
Summary: In this study, a novel axial strain sensor based on OMC operating at DTP was designed to achieve high-sensitivity measurements of axial strain. The sensor was found to be highly sensitive to axial strains when the effective refractive index difference between the odd and even modes in the coupling region of the OMC is equal to zero, as confirmed by theoretical calculations and experimental results.
IEEE SENSORS JOURNAL
(2022)
Article
Engineering, Environmental
Pengwei Chen, Yunyun Huang, Ye Bo, He Liang, Aoxiang Xiao, Bai-Ou Guan
Summary: This study presents the development of a 3D plasmonic nanointerface to enhance the detection and sizing of single nanoparticles in real time using optical microfibers. The integration of Cu3-xP nanocrystals into a Cu-BTC framework and tuning the localized-surface plasmon resonance allows for the binding of target nanoparticles on the microfiber. By confining the resonance field on the microfiber with three dimensions, the sensor overcomes its sensitivity limit and enables the detection and sizing of individual nanoparticles.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Wanling Wu, Huakang Yu, Chunhua Wang, Zhiyuan Li
Summary: Efficient mode conversion from standard single-mode fiber to subwavelength-diameter microfiber was achieved using a tapered fiber, resulting in a significant change in mode area within a short length. This method is important for the development of hybrid photonic systems.
Article
Optics
Zhicheng Wang, Zheng Peng, Yuqing Zhang, Yilu Wu, Jiagui Wu, Junbo Yang
Summary: This research presents the design of an optical power splitter with ultra-broadband and ultra-low insertion loss using two inverse design algorithms for staged optimization. The Y-junction photonic power splitter achieves a 700 nm wavelength bandwidth (from 1200 nm to 1900 nm) with a 0.2 dB insertion loss, corresponding to a 93 THz frequency bandwidth. The average insertion loss in the valuable C-band is approximately -0.057 dB. Additionally, a comprehensive comparison of insertion loss performance for different types and sizes of curved waveguides is provided, along with cases of 1:4 and 1:6 cascaded power splitters. These scalable Y-junction splitters offer new alternatives for high-performance photonic integration.
Article
Engineering, Electrical & Electronic
Youlian Wei, Wenchao Zhou, Yue Wang, Kaiwei Li, Yihui Wu
Summary: This study presents a two-step fabrication method for OMCs with precisely controlled DTPs, showing that the DTP can be accurately tuned in both water and high refractive index liquid media by controlling the reaction time. Experimental results demonstrate that OMCs fabricated using this method can serve as ultrasensitive RI sensors and biosensors for CEA.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Junyang Lu, Zhenrong Zhang, Yang Yu, Shangpeng Qin, Fangyuan Zhang, Minwei Li, Qiang Bian, Mengxiao Yin, Junbo Yang
Summary: In this study, a reflective optical fiber sensor based on a PDMS-sealed optical microfiber coupler combined with a sagnac loop was proposed to achieve simultaneous measurement of temperature and pressure in seawater. The sensor showed improved sensitivity and structural stability compared to bare fiber sensors. Experimental results demonstrated the sensor's ability to demodulate temperature and pressure sensing simultaneously, with average errors of 1.61% and 5.02%, respectively. The sensor's compact structure, ease of fabrication, high sensitivity, fast response speed, and high stability make it comparable to existing TD sensors for marine environmental monitoring and ocean dynamics research.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Taiji Dong, Bingkun Gao, Xu Liu, Yunkai Wang, Chunlei Jiang, Xiufang Wang, Wendi Yan, Yang Zhang
Summary: In this study, a sensor based on an optical microfiber coupler (OMC) and a Sagnac ring is proposed to achieve large-range and high-sensitivity strain and vibration measurements. The sensor takes advantage of the sensitivity of the evanescent field around the OMC and the tensile resistance of the Sagnac ring, and experimental results demonstrate its effectiveness in strain and vibration measurements.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Shengyao Xu, Weijie Chang, Yiyang Luo, Wenjun Ni, Yu Zheng, Lei Wei, Zhilin Xu, Zhenggang Lian, Yang'an Zhang, Yongqing Huang, Perry Ping Shum
Summary: The optical microfiber-based refractometer relies on modal interference near the dispersion turning point (DTP) and has attracted significant research interest due to its ultrahigh sensitivity. However, DTP-based sensors have reported low fabrication tolerance and narrow operation bandwidth, limiting practical applications with higher refractive index sensitivities. To address this challenge, a specially-designed single stress-applying fiber (SSAF) has been used to manipulate and optimize mode dispersion, significantly reducing wavelength sensitivity of the group effective refractive index difference. This approach dramatically broadens the operation bandwidth to 500 nm, allowing for a wide range of optional probing wavelengths and high fabrication tolerance.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
N. K. Thipparapu, Shaiful Alam, Yu Wang, S. Pidishety, David J. Richardson, Jayanta K. Sahu
Summary: An all-fiber actively mode-locked Bismuth-doped fiber laser based on an acousto-optic modulator is proposed, which can achieve higher harmonic mode-locking and wavelength tuning. The laser has high output power and stability.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Optics
Kerr Johnson, Pablo Castro-Marin, Carl Farrell, Ian A. Davidson, Qiang Fu, Gregory T. Jasion, Natalie Wheeler, Francesco Poletti, David J. Richardson, Derryck T. Reid
Summary: High-resolution multi-species spectroscopy is achieved by delivering broadband mid-infrared light through a silica-based hollow-core optical fiber. The absorptions of gases within the fiber core are observed and their concentrations are obtained. Further spectroscopy of different molecules contained in a Herriott cell after the fiber is enabled by nullifying the contributions of the absorbed gases.
Article
Nanoscience & Nanotechnology
Di Lin, Yutong Feng, Zhengqi Ren, David J. Richardson
Summary: Efficient generation of high-peak-power femtosecond optical vortex pulses with selectable topological charge has been successfully demonstrated from a fiber oscillator using a few-mode polarization-maintaining ytterbium-doped fiber. This unprecedented performance level is of great interest for applications such as materials processing and imaging.
Article
Optics
H. C. H. Mulvad, S. Abokhamis Mousavi, V. Zuba, L. Xu, H. Sakr, T. D. Bradley, J. R. Hayes, G. T. Jasion, E. Numkam Fokoua, A. Taranta, S. -U. Alam, D. J. Richardson, F. Poletti
Summary: Anti-resonant hollow-core fibres offer lower nonlinearity and comparable characteristics to conventional fibres. We successfully demonstrated the delivery of 1 kW near-diffraction-limited continuous-wave laser light over a 1 km distance using a single-mode hollow-core fibre. This technology has potential applications in manufacturing, subsurface drilling, as well as sensing, particle acceleration, and gravitational wave detection.
Article
Multidisciplinary Sciences
Deming Kong, Yong Liu, Zhengqi Ren, Yongmin Jung, Chanju Kim, Yong Chen, Natalie Wheeler, Marco N. Petrovich, Minhao Pu, Kresten Yvind, Michael Galili, Leif K. Oxenlowe, David J. Richardson, Hao Hu
Summary: Researchers have developed an on-chip continuous spectral translation method that leverages existing commercial transceivers to unlock potential new wavelength bands. Using AlGaAsOI nanowaveguides as spectral translators, they demonstrated the potential for coherent transmission in the 2-mu m band and achieved high-speed transmission over a 1.15-km hollow-core fiber.
NATURE COMMUNICATIONS
(2022)
Article
Optics
Xi Zhang, Zitong Feng, David Marpaung, Eric Numkam Fokoua, Hesham Sakr, John Richard Hayes, Francesco Poletti, David John Richardson, Radan Slavik
Summary: Analogue signal transmission is preferred in many applications due to lower cost or superior performance. However, the performance of long analogue photonics links using standard single-mode fibres (SSMF) is limited by impairments such as stimulated Brillouin scattering, chromatic dispersion, and Kerr nonlinearity. This study proposes using hollow-core optical fibres to address these shortcomings and demonstrates significant improvements in performance compared to SSMF links.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Di Lin, Duanyang Xu, Jing He, Yutong Feng, Zhengqi Ren, Raghuraman Sidharthan, Yongmin Jung, Seongwoo Yoo, David J. Richardson
Summary: A high-energy and high-average power Mamyshev oscillator based on a high performance large-mode-area step-index germanosilicate-cladding Yb-doped fiber is demonstrated. This fiber oscillator can directly generate the highest pulse energy with sub-100 fs duration.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Thomas W. Kelly, Ian A. Davidson, Charles Warren, William S. M. Brooks, Michael J. Foster, Francesco Poletti, David J. Richardson, Peter Horak, Natalie V. Wheeler
Summary: This study demonstrates recent progress in the development of a Raman gas sensor using a single cladding ring anti-resonant hollow core micro-structured optical fiber and a low power pump source. The fiber provides low attenuation and wide bandwidth in the visible spectral region, and selective core pressurization scheme further enhances the Raman signal. Direct detection of methane and hydrogen at low concentrations is achieved by exploiting longer lengths of fiber.
Article
Optics
Eric Numkam Fokoua, Seyed Abokhamis Mousavi, Gregory T. Jasion, David J. Richardson, Francesco Poletti
Summary: In recent years, advances in hollow-core optical fiber technology have resulted in reduced attenuation levels comparable to solid-core fibers. This has renewed interest in the technology and the expectation of achieving highly transparent light propagation across all wavelengths. This review examines the physical mechanisms driving attenuation in both legacy photonic bandgap and antiresonant hollow-core fibers. It discusses intrinsic and extrinsic loss mechanisms, as well as provides scaling rules and design guidelines for low-loss hollow-core fibers.
ADVANCES IN OPTICS AND PHOTONICS
(2023)
Article
Engineering, Electrical & Electronic
Xuhao Wei, Austin Taranta, Bo Shi, Meng Ding, Zitong Feng, David J. Richardson, Francesco Poletti, Radan Slavik
Summary: Thermal phase sensitivity in optical fibers is undesirable for fiber interferometers and applications requiring a fixed phase. Using hollow core fiber reduces thermal phase sensitivity, and coiling the fiber further reduces this sensitivity significantly.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Optics
Zitong Feng, Hesham Sakr, John R. Hayes, Eric Numkam Fokoua, Meng Ding, Francesco Poletti, David J. Richardson, Radan Slavik
Summary: Optical fibers with a low thermal coefficient have been developed for frequency and timing transmission. A new hollow core fiber with a thin acrylate coating has been shown to have a stable thermal coefficient over a wide temperature range and can be insensitive to temperature around -134 degrees C.
Article
Engineering, Electrical & Electronic
Nicolas K. Fontaine, Joel Carpenter, Simon Gross, Sergio Leon-Saval, Yongmin Jung, David J. Richardson, Rodrigo Amezcua-Correa
Summary: This article reviews four-mode multiplexing and manipulation technologies in the context of space-division multiplexing optical communication systems. These technologies include multiplane light conversion, fused fiber devices, 3-D waveguides fabricated using ultrafast laser inscription, and free-space imaging systems. Each technology has its own strengths and applications, enabling complex spatial mode transformations and high-power handling.
PROCEEDINGS OF THE IEEE
(2022)
Article
Optics
Kunhao Ji, Di Lin, Ian A. Davidson, Siyi Wang, Joel Carpenter, Yoshimichi Amma, Yongmin Jung, Massimiliano Guasoni, David J. Richardson
Summary: Higher-order Poincare sphere (HOPS) beams with spatially variable polarization and phase distributions have unique applications in optical communication and microscopy. Generating these beams with high peak power from compact laser systems remains a challenge. In this study, we demonstrate the controlled generation of HOPS beams using coherent beam combination from an Yb-doped multicore fiber (MCF) amplifier, achieving peak powers up to 14 kW for similar to 92 ps pulses.
PHOTONICS RESEARCH
(2023)
Article
Engineering, Electrical & Electronic
John D. Downie, Yongmin Jung, Sergejs Makovejs, Merrion P. Edwards, David J. Richardson
Summary: We compare different options for amplification in trans-oceanic repeatered submarine systems using multicore fiber transmission. Our analysis focuses on relative cable capacity and relative system cost/bit. We evaluate the optical performance of parallel single-core erbium-doped fiber amplifiers (SC-EDFAs) and multicore erbium-doped fiber amplifiers (MC-EDFAs) with various configurations. Key parameters like noise figure, amplifier bandwidth, electrical-to-optical conversion efficiency, and amplifier cost impact the expected capacity and cost/bit performance. Our findings show that MC-EDFAs with either core- or cladding-pumping may offer lower cost/bit compared to parallel SC-EDFAs, but cladding-pumping could reduce cable capacities due to higher noise figure and potentially lower amplifier bandwidth.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Yongmin Jung, Jing Meng, Kerrianne Harrington, Hesham Sakr, Ian A. Davidson, Sijing Liang, Gregory Jasion, Francesco Poletti, David J. Richardson
Summary: This paper investigates two methods for the direct interconnection of hollow-core fibers (HCFs) with laser diodes or photodiodes. The research findings show that direct butt coupling has low efficiency due to mode field diameter (MFD) mismatch, but efficiency can be improved by using a graded-index fiber based all-fiber MFD converter. On the other hand, a two-lens system enables extremely high coupling efficiency.
OPTICAL FIBER TECHNOLOGY
(2023)
