A5100425292- Advanced Fiber Optic Sensors
- Advanced Fiber Laser Technologies
- Photonic and Optical Devices
- Random lasers and scattering media
- Orbital Angular Momentum in Optics
- Photonic Crystal and Fiber Optics
- Quantum optics and atomic interactions
- Neural Networks and Reservoir Computing
- Optical Network Technologies
- Mechanical and Optical Resonators
- Semiconductor Lasers and Optical Devices
- Magneto-Optical Properties and Applications
- Advanced Photonic Communication Systems
- Solid State Laser Technologies
- Photoacoustic and Ultrasonic Imaging
- Nanofabrication and Lithography Techniques
- Plasmonic and Surface Plasmon Research
- Atomic and Subatomic Physics Research
- Nonlinear Dynamics and Pattern Formation
- Advanced MEMS and NEMS Technologies
- Organic Electronics and Photovoltaics
- Optical Coherence Tomography Applications
- Organic Light-Emitting Diodes Research
- Underwater Vehicles and Communication Systems
- Cold Atom Physics and Bose-Einstein Condensates
Shanghai University
2016-2025
Southern University of Science and Technology
2023-2025
Shanghai Research Institute of Materials
2024
Northern Jiangsu People's Hospital
2024
Changsha University
2024
Zhejiang Lab
2024
Beijing Jiaotong University
2023
National University of Singapore
2023
Shenzhen Institutes of Advanced Technology
2017-2022
Chinese Academy of Sciences
2017-2022
We demonstrate the fabrication of long-period fiber gratings (LPFGs) written in two-mode (TMF) by CO2 laser. Both uniform and tilted LPFGs were fabricated to provide light coupling between LP01 mode LP11 with a efficiency more than 99%. The writing bandwidth LPFG converter can be adjusted changing tilt angle TMF-LPFGs. torsion sensitivity conventional converters measured 0.37 nm/(rad/m) 0.50 nm/(rad/m), respectively. Two orthogonal vector modes (the HEeven 21and HEodd 21 modes) corresponding...
We demonstrate the fabrication of helical long-period grating (HLPG) in a two-mode fiber (TMF) with CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laser. The torsion characteristics gratings are experimentally investigated. It was found that resonance wavelength TMF-HLPG linearly shifts twist sensitivity 0.47 nm/(rad/m), which is an order magnitude higher than conventional (LPFGs). temperature TMF-HPFG measured to be 23.9 pm/°C, one...
A novel highly sensitive ultrasound sensor based on a random fiber laser is proposed and demonstrated for the first time, to best of our knowledge. The constructed with erbium-doped gain. grating provides random-distributed feedback acts as an sensing head. can operate in single-mode lasing scenario, which offers linear pure temporal responses broadband ultrasonic acoustic emission from 20 kHz 0.8 MHz. multiple-interfering reflection spectrum large number steep peak areas over broad spectral...
A chiral long-period grating (CLPG) was fabricated successfully by scanning CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laser in a twisted conventional single-mode fiber. The strong mode coupling can be achieved short length. sensing characteristics of the CLPGs were investigated experimentally. Compared with fiber gratings, found to have similar temperature and refractive index sensitivities much higher torsion, bending, strain...
Narrow-linewidth multi-wavelength fiber lasers are of significant interests for fiber-optic sensors, spectroscopy, optical communications, and microwave generation. A novel narrow-linewidth dual-wavelength random laser with single-mode operation, based on the semiconductor amplifier (SOA) gain, is achieved in this work first time, to best our knowledge. simplified theoretical model established characterize such kind laser. The inhomogeneous gain SOA mitigates mode competition significantly...
Multi-wavelength (MW) laser sources with high optical signal-to-noise ratios (OSNR) are of great interest for communications ultrahigh data capacity as well microwave and terahertz photonics. In this paper, we report the first demonstration MW Brillouin random fiber in telecom spectral window around 1.5 μm based on a unique grating (RFG). Random feedback by enhanced distributed Rayleigh scattering from RFG basically enables high-efficiency lasing resonance Stokes wave via stimulated fibers....
A multilongitudinal mode fiber laser sensor formed by two Bragg gratings and a piece of erbium-doped is first proposed validated experimentally. When the strain applied on sensor, cavity stretched, which leads to change round-trip frequency. Thus can be obtained measuring beat frequency resonant cavity. The found characterized with simplicity, easy setup, high resolution, low-cost demodulation, good stability. Experimental results show that has sensitivity −1.1 KHz/μϵ root-mean-square...
We report superluminal propagation in optical fibers using Brillouin lasing oscillation a ring cavity. Negative group velocity through 10-m single mode fiber has been experimentally demonstrated. An advancement of 221.2 ns was observed before the input signal, which achieved with very high slope efficiency $211.3\text{ }\text{ }\mathrm{ns}/\mathrm{dB}$. This indicates that this way is suitable for long-distance low-loss via fibers. Correspondingly, $\ensuremath{-}0.151c$ and index...
A watt-level ultrahigh optical signal-to-noise ratio (OSNR) single-longitudinal-mode (SLM) tunable Brillouin fiber laser (BFL) has been demonstrated.By optimizing the length of single mode (SMF) cavity at 11m and its output sixty percent, 1.04 W power, as well stable SLM operation is obtained 2.24 pump power. The pass BFL advantage that frequency doesn't need to match mode, thus stability greatly improved. As only SMF used in cavity, operate wavelength can be without restriction from self...
Highly sensitive and broadband ultrasound (tens of megahertz) detectors can extend the capabilities photo-acoustic imaging in biomedical application nondestructive test inspection. Here ultra-compact fiber-based multi-mode dual-cavity Fabry–Perot interferometer (DC-FPI) sensors are proposed by splicing three sections cleaved standard single-mode fibers with fiber off-core cross section middle. The contrasts, reflectivity, linewidths DC-FPIs have been comprehensively characterized. frequency...
Vortex beams have attracted much attention in recent years due to unique features of the phase or polarization singularity center part beams. Various applications been explored by vortex including optical communication, tweezer, etc. Especially, for sensing emerged. Compared with traditional Gaussian beams, enable degree freedom controlling spin and orbital polarization. In this review article, we discussed theory vortices, then summarized beam generation fiber their applications. It is...
Despite its important role in understanding ultrafast spin dynamics and revealing novel spin/orbit effects, the mechanism of terahertz (THz) emission from a single ferromagnetic nanofilm upon femtosecond laser pump still remains elusive. Recent experiments have shown exotic symmetry, which is not expected routinely adopted demagnetization. Here, by developing bidirectional pump-THz spectroscopy associated symmetry analysis method, we set benchmark for experimental distinction THz induced...
A low-noise Brillouin random fiber laser (BRFL) based on dynamic grating (DFG)-assisted self-injection locking (SIL) as a carrier for coherent communication is proposed and experimentally demonstrated. The utilization of the DFG-based SIL basically guarantees an innovative purification ultra-narrow-linewidth radiation after removal residual modes from gain competition, enabling unprecedented long-term frequency-stabilized lasing resonance over record 30 s. Consequently, relative intensity...
A novel torsion sensor is proposed and demonstrated by detecting the modal interference pattern rotation of a helical sidehole fiber (HSHF). The HSHF successfully fabricated rotating drawing preform with side-hole drilling, which supports two modes. Based on coupling analysis, single-mode precisely offset-spliced to one end evenly excite LP<sub>01</sub> LP<sub>11</sub> Subsequently, subjected torsion, its response evaluated analyzing output pattern, demonstrates high linear correlation...
<title>Abstract</title> Background Fitz-Hugh-Curtis syndrome (FHCS) is a form of perihepatic inflammation, frequently associated with pelvic inflammatory disease (PID), primarily affecting the liver capsule without significant involvement hepatic parenchyma. This study aims to investigate clinical characteristics, treatment methods, and outcomes FHCS provide diagnostic therapeutic insights for clinicians. Methods retrospective analysis reviewed data 7 patients diagnosed at Southern...
We proposed and experimentally demonstrated an extremely simple feasible slow-light technique to achieve tunable optical delay by using the Er/Yb codoped fiber Bragg grating (FBG). The signal light experiences strong dispersion when it is launched into reflection edge of FBG, group value determined wavelength pump power. In experiment, a controllable 0.9 ns can be obtained through changing 980 nm velocity slowed down 5.6x10(7) m/s, which 19% speed in free space. It provides very approach...
We report a high-efficiency (25%) Brillouin random fiber laser (BRFL) with gain medium of 2-km polarization maintaining (PMF) as well distributed Rayleigh scattering feedback from 500-m PMF. The characteristics lasing efficiency and relative intensity noise (RIN) have been comprehensively studied comparing the BRFLs half-open ring cavity bidirectional pumping linear open configuration. enhanced using PMF-BRFL enables sub-kHz linewidth, lower phase fluctuation frequency jitter locked pump...
An optical fiber acoustic sensor based on nonstandard fused coupler and aluminum foil is proposed experimentally demonstrated. Acoustic vibration measured by detecting the insertion loss of coupler. As number coupling cycle increases, sensitivity multicycle coupler-based sensors to could be improved. Under same experimental conditions input light power <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math...
A narrow-linewidth multiwavelength Brillouin random fiber laser (MW-BRFL) was experimentally demonstrated and characterized, which achieved by mutually combining amplification with randomly distributed Rayleigh feedback in optical fibers. By cascading process through a sub-fiber loop, up to six orders Stokes emissions simultaneously resonate coherent lasing fashion under the acoustic coupling of stimulated scattering presence scattered feedback, acts as an filter high reflection coefficient...
We demonstrate that a semiconductor laser perturbed by the distributed feedback from fiber random grating can emit light chaotically without time delay signature. A theoretical model is developed based on Lang-Kobayashi in order to numerically explore chaotic dynamics of diode subjected feedback. It predicted superior single reflection suppressing time-delay In experiments, massive number feedbacks with randomly varied delays induced introduce large numbers external cavity modes into laser,...
An all-silica Fabry-Perot interferometer (FPI) based on a microbubble for high-pressure and high-temperature measurements is proposed demonstrated. The microbubble-based air cavity fabricated using hollow silica tube single-mode optical fiber pressure sensing. suitable thickness between the two end faces of enables to be used temperature wavelength shift reflection spectrum versus linear, sensitivity reaches -5.083 nm/MPa at room (20 °C) within range 0 - 4 MPa. 12.715 pm/°C 20 700 °C. very...
A linearly polarized Brillouin random fiber laser (LP-BRFL) with distributed feedback along 2 km polarization-maintaining fibers (PMFs) is demonstrated. The was built up using a bidirectional pumping mechanism in an all-PMF configuration, yielding radiation 8% power efficiency and more than 25 dB polarization extinction ratio. high lasing achieved due to the polarization-matched amplification kilometer long PMFs. relative intensity noise thermal-induced frequency of this have also been...
We demonstrate the fabrication of helical long-period gratings (HLPGs) with periodic index modulation by twisting double-clad fiber (DCF) while was exposed CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laser. Torsion, bending, surrounding refractive index, temperature and axial strain characteristics fabricated DCF-HLPG were investigated experimentally. The found to have a high torsion sensitivity -0.384 nm/(rad/m) bending 18.112...