A novel design is proposed for highly sensitive surface-plasmon-resonance sensors. The sensor is based on a microstructured optical fiber with two layers of annular-shaped holes. A gold layer is deposited on the inner...A novel design is proposed for highly sensitive surface-plasmon-resonance sensors. The sensor is based on a microstructured optical fiber with two layers of annular-shaped holes. A gold layer is deposited on the inner surface of the second hole-layer, in which the holes have several micrometers thickness in size, facilitating analyte infiltration and metal layer deposition. In the first layer of holes, the sector-ring^shaped arms, used as supporting strips, are utilized to tune the resonance depth of the sensor. Numerical results indicate that the sensor operation wavelength can be tuned across the C+L-band. The spectral sensitivity of 1.0.104 nm. RIU-1 order of magnitude and a detection limit of 1.0.10-4 RIU order are demonstrated over a wide range of analyte refractive index from 1.320 to 1.335.展开更多
High flatness, wide bandwidth, and high-coherence properties of supercontinuum(SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, sin...High flatness, wide bandwidth, and high-coherence properties of supercontinuum(SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, since special dispersion profiles are required, especially when pump pulses with duration over 100 fs are employed. We propose an all-solid microstructured fiber composed only of hexagonal glass elements. The optimized fiber possesses an ultraflat all-normal dispersion profile, covering a wide wavelength interval of approximately 1.55 μm. An SC spectrum spanning from approximately 1030 to 2030 nm(corresponding to nearly one octave) with flatness<3 dB is numerically generated in the fiber with 200 fs pump pulses at 1.55 μm. The results indicate that the broadband ultraflat SC sources can be all-fiber and miniaturized due to commercially achievable 200-fs fiber lasers. Moreover, the SC pulses feature high coherence and a single pulse in the time domain, which can be compressed to 13.9-fs pulses with high quality even for simple linear chirp compensation. The Fourier-limited pulse duration of the spectrum is 3.19 fs, corresponding to only 0.62 optical cycles.展开更多
We report on fiber Bragg gratings in all-solid photonie bandgap fiber that was composed of a triangular array of high-index Ge-doped rods in pure silica background with fluorine-doped index-depressed layer surrounding...We report on fiber Bragg gratings in all-solid photonie bandgap fiber that was composed of a triangular array of high-index Ge-doped rods in pure silica background with fluorine-doped index-depressed layer surrounding the Ge-doped rod. Fiber Bragg gratings were photowritten with 193 nm ArF excimer laser and characterized for their response to strain, temperature, bending, and torsion. These gratings couple light from the forward core mode to not only backward core mode but also backward rod modes. This results in multiple resonance peaks in the reflection spectrum. All resonance wavelengths exhibited the same temperature and strain response with coefficient similar to that of Bragg gratings in standard single-mode fiber. The strength of the resonance peaks corresponding to the backward rod modes showed high sensitivity to bending and torsion.展开更多
We demonstrate a deep-learning-based fiber imaging system that can transfer real-time artifact-free cell images through a meter-long Anderson localizing optical fiber.The cell samples are illuminated by an incoherent ...We demonstrate a deep-learning-based fiber imaging system that can transfer real-time artifact-free cell images through a meter-long Anderson localizing optical fiber.The cell samples are illuminated by an incoherent LED light source.A deep convolutional neural network is applied to the image reconstruction process.The network training uses data generated by a setup with straight fiber at room temperature(∼20°C)but can be utilized directly for high-fidelity reconstruction of cell images that are transported through fiber with a few degrees bend or fiber with segments heated up to 50°C.In addition,cell images located several millimeters away from the bare fiber end can be transported and recovered successfully without the assistance of distal optics.We provide evidence that the trained neural network is able to transfer its learning to recover images of cells featuring very different morphologies and classes that are never“seen”during the training process.展开更多
A multi-direction bending sensor based on spot pattern demodulation of a dual-hole fiber(DHF)is proposed.By using the interference and scattering in a DHF,the related multidirectional variations can be captured by the...A multi-direction bending sensor based on spot pattern demodulation of a dual-hole fiber(DHF)is proposed.By using the interference and scattering in a DHF,the related multidirectional variations can be captured by the optical field.Furthermore,the multi-directional bending characteristics of the fiber are quantitatively described by the pattern of the output light spot,achieving multidirectional bending sensing.In addition,considering the subtle changes in the deformation patterns over time,a convolutional neural network(CNN)model based on deep learning is introduced for accurate recognition and prediction of the bending angle.The experimental results show that the sensor can perceive different bending angles in four directions.These outstanding results indicate that the multi-directional bending sensor based on dual-hole interference pattern decoding has potential applications in multi-directional quantitative sensing and artificial intelligence perception.展开更多
Fiber optofluidic laser(FOFL)integrates optical fiber microcavity and microfluidic channel and provides many unique advantages for sensing applications.FOFLs not only inherit the advantages of lasers such as high sens...Fiber optofluidic laser(FOFL)integrates optical fiber microcavity and microfluidic channel and provides many unique advantages for sensing applications.FOFLs not only inherit the advantages of lasers such as high sensitivity,high signal-to-noise ratio,and narrow linewidth,but also hold the unique features of optical fiber,including ease of integration,high repeatability,and low cost.With the development of new fiber structures and fabrication technologies,FOFLs become an important branch of optical fiber sensors,especially for application in biochemical detection.In this paper,the recent progress on FOFL is reviewed.We focuse mainly on the optical fiber resonators,gain medium,and the emerging sen sing applicatio ns.The prospects for FOFL are also discussed.We believe that the FOFL sensor provides a promising technology for biomedical analysis and environmental monitoring.展开更多
基金supported by the Program Sponsored for Scientific Innovation Research of College Graduates in Jangsu Province,China(No.CXZZ12 0656)the Qing Lan Project of Jiangsu Province,Open Fund Supported by Jiangsu Provincial Key Laboratory for Science and Technology of Photon Manufacturing(Jiangsu University)of China(No.GZ201201)
文摘A novel design is proposed for highly sensitive surface-plasmon-resonance sensors. The sensor is based on a microstructured optical fiber with two layers of annular-shaped holes. A gold layer is deposited on the inner surface of the second hole-layer, in which the holes have several micrometers thickness in size, facilitating analyte infiltration and metal layer deposition. In the first layer of holes, the sector-ring^shaped arms, used as supporting strips, are utilized to tune the resonance depth of the sensor. Numerical results indicate that the sensor operation wavelength can be tuned across the C+L-band. The spectral sensitivity of 1.0.104 nm. RIU-1 order of magnitude and a detection limit of 1.0.10-4 RIU order are demonstrated over a wide range of analyte refractive index from 1.320 to 1.335.
基金National Natural Science Foundation of China(NSFC)(61475171,11374084,61705244,61307056)Natural Science Foundation of Shanghai(17ZR1433900,17ZR1434200)
文摘High flatness, wide bandwidth, and high-coherence properties of supercontinuum(SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, since special dispersion profiles are required, especially when pump pulses with duration over 100 fs are employed. We propose an all-solid microstructured fiber composed only of hexagonal glass elements. The optimized fiber possesses an ultraflat all-normal dispersion profile, covering a wide wavelength interval of approximately 1.55 μm. An SC spectrum spanning from approximately 1030 to 2030 nm(corresponding to nearly one octave) with flatness<3 dB is numerically generated in the fiber with 200 fs pump pulses at 1.55 μm. The results indicate that the broadband ultraflat SC sources can be all-fiber and miniaturized due to commercially achievable 200-fs fiber lasers. Moreover, the SC pulses feature high coherence and a single pulse in the time domain, which can be compressed to 13.9-fs pulses with high quality even for simple linear chirp compensation. The Fourier-limited pulse duration of the spectrum is 3.19 fs, corresponding to only 0.62 optical cycles.
基金supported by the Key Project of National Natural Science Foundation of China under Grant No. 60736039.
文摘We report on fiber Bragg gratings in all-solid photonie bandgap fiber that was composed of a triangular array of high-index Ge-doped rods in pure silica background with fluorine-doped index-depressed layer surrounding the Ge-doped rod. Fiber Bragg gratings were photowritten with 193 nm ArF excimer laser and characterized for their response to strain, temperature, bending, and torsion. These gratings couple light from the forward core mode to not only backward core mode but also backward rod modes. This results in multiple resonance peaks in the reflection spectrum. All resonance wavelengths exhibited the same temperature and strain response with coefficient similar to that of Bragg gratings in standard single-mode fiber. The strength of the resonance peaks corresponding to the backward rod modes showed high sensitivity to bending and torsion.
文摘We demonstrate a deep-learning-based fiber imaging system that can transfer real-time artifact-free cell images through a meter-long Anderson localizing optical fiber.The cell samples are illuminated by an incoherent LED light source.A deep convolutional neural network is applied to the image reconstruction process.The network training uses data generated by a setup with straight fiber at room temperature(∼20°C)but can be utilized directly for high-fidelity reconstruction of cell images that are transported through fiber with a few degrees bend or fiber with segments heated up to 50°C.In addition,cell images located several millimeters away from the bare fiber end can be transported and recovered successfully without the assistance of distal optics.We provide evidence that the trained neural network is able to transfer its learning to recover images of cells featuring very different morphologies and classes that are never“seen”during the training process.
基金supported by the Basic and Applied Basic Research Foundation of Guangdong Province(No.2022A1515110480)the National Natural Science Foundation of China(No.62205057)the Dongguan Science and Technology of Social Development Program(No.20231800903222).
文摘A multi-direction bending sensor based on spot pattern demodulation of a dual-hole fiber(DHF)is proposed.By using the interference and scattering in a DHF,the related multidirectional variations can be captured by the optical field.Furthermore,the multi-directional bending characteristics of the fiber are quantitatively described by the pattern of the output light spot,achieving multidirectional bending sensing.In addition,considering the subtle changes in the deformation patterns over time,a convolutional neural network(CNN)model based on deep learning is introduced for accurate recognition and prediction of the bending angle.The experimental results show that the sensor can perceive different bending angles in four directions.These outstanding results indicate that the multi-directional bending sensor based on dual-hole interference pattern decoding has potential applications in multi-directional quantitative sensing and artificial intelligence perception.
基金the financial support from the National Natural Science Foundation of China(Grant No.61875034)the 111 Project(Grant No.B14039)Seeding Project of Scientific and Technical Innovation of Sichuan Province(Grant No.2020107).
文摘Fiber optofluidic laser(FOFL)integrates optical fiber microcavity and microfluidic channel and provides many unique advantages for sensing applications.FOFLs not only inherit the advantages of lasers such as high sensitivity,high signal-to-noise ratio,and narrow linewidth,but also hold the unique features of optical fiber,including ease of integration,high repeatability,and low cost.With the development of new fiber structures and fabrication technologies,FOFLs become an important branch of optical fiber sensors,especially for application in biochemical detection.In this paper,the recent progress on FOFL is reviewed.We focuse mainly on the optical fiber resonators,gain medium,and the emerging sen sing applicatio ns.The prospects for FOFL are also discussed.We believe that the FOFL sensor provides a promising technology for biomedical analysis and environmental monitoring.