- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Hybridizing graphene and photonic crystal fibre
摘要： While the ability to increase the light–matter interaction by depositing graphene inside the air holes of a long length of photonic crystal fibre is worth celebrating, cautious optimism is called for when we begin to discuss the industrialization of graphene-based fibre-optic components.
关键词： photonics,graphene,photonic crystal fibre,light–matter interaction
更新于2025-09-23 15:19:57
-
Amphibious sensor of temperature and refractive index based on D-shaped photonic crystal fibre filled with liquid crystal
摘要： A D-shaped photonic crystal fibre filled with liquid crystal was demonstrated as an amphibious sensor for detection of both temperature and refractive index, when combined with plasma materials. Specifically, the optical component is implanted into a complete optical system ensuring modulation of the external electric field. When the refractive index of the external solution changes from 1.0 to 1.6, the y-polarised mode has a loss spectrum with a wavelength sensitivity of up to 2275 nm/RIU, and the corresponding amplitude sensitivity is ?88.2RIU?1. When the perceived temperature changes from 15°C to 50°C, the temperature of the sensor is correspondingly expressed as the maximum wavelength sensitivity of 9.09 nm/°C and the amplitude sensitivity of ?0.311°C?1. In addition, the actual micro-operation processes have been studied in detail, such as polishing depth, coating thickness and coating method. This provides practical ideas for real-time sensing analysis that requires harsh environments.
关键词： surface plasmon resonance,sensitivity,Fibre optics sensors,photonic crystal fibre
更新于2025-09-16 10:30:52
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Soliton Self-Compression and UV Dispersive Wave Emission in Compact Hollow Capillary Systems
摘要： Soliton dynamics underlie a wide range of phenomena in nonlinear fibre optics. In particular, higher-order solitons in gas-filled hollow-core photonic crystal fibre (HC-PCF) have been applied to self-compression of ultrafast laser pulses [1] and the generation of widely tuneable resonant dispersive waves (RDW) from the vacuum ultraviolet (VUV) to the visible spectral range [2]. We recently demonstrated that by moving to long, large-core hollow capillary fibres (HCF) and shorter driving pulses, these effects can be scaled by up to three orders of magnitude in pulse energy, providing unprecedented peak power in ultrafast VUV pulses as well as a route towards terawatt-scale optical attosecond pulses [3]. Here we show that by further decreasing the initial pulse duration, high-energy soliton dynamics can be obtained in HCF as short as 35 cm.
关键词： Soliton dynamics,ultrafast laser pulses,hollow-core photonic crystal fibre,nonlinear fibre optics,resonant dispersive waves
更新于2025-09-12 10:27:22
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Reconstruction of Guided Helical Bloch Modes in Twisted Coreless Photonic Crystal Fibre using Bessel Beams
摘要： Light beams carrying orbital angular momentum (OAM) are of fundamental interest in many fields of research. Recently it has been reported that helical Bloch modes (HBMs) carrying multiple values of OAM are guided in chirally twisted photonic crystal fibre (PCF), even when there is no core. HBMs are not supported by conventional waveguides and would be very difficult to realise using multi-beam interference. Here we report the first complete experimental characterisation of the phase and amplitude of the complex HBM fields in twisted coreless PCF. We compare the measurements with finite element simulations, based on precise scanning electron micrographs of the fibre structure, obtaining excellent agreement. We then expand the numerically calculated HBM fields as a series of Bessel beams, allowing us to calculate the strengths and azimuthal orders of the HBM harmonics with a fidelity greater than 95%.
关键词： Bessel beams,helical Bloch modes,orbital angular momentum,photonic crystal fibre
更新于2025-09-12 10:27:22
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Dual-Colour-Pump Broadband CARS in Single-Ring Gas-Filled Photonic Crystal Fibre
摘要： Selective detection and chemical analysis of trace gases at concentration levels of parts per million (ppm) and below is of critical importance in environmental monitoring and medicine. Spectroscopic techniques offer high gas-type selectivity and are widely used for measuring the concentration of specific molecular species. Raman spectroscopy provides two key advantages. First, the pump wavelength can be freely chosen, independently of the absorption lines of the gas. Second, the highest Raman frequency shift of any gas is the vibrational transition of H2 at 125 THz, which means that all known Raman active molecules can be detected with one spectrometer. We report coherent anti-Stokes Raman spectroscopy (CARS) in single-ring hollow-core photonic crystal fibre (SR-PCF) using a dual-colour pump. The long collinear path-length offered by SR-PCF strongly enhances the efficiency of the Raman interactions, and furthermore the gas-filled SR-PCF has a zero dispersion wavelength which is pressure tuneable. By selecting an appropriate pressure, the dispersion can be arranged to be anomalous in the visible and at the same time normal in the ultraviolet. Under these circumstances, by fine-tuning the pressure to minimize dephasing, the Raman coherence prepared by seeded pumping in the visible can be used for phase-matched generation of an anti-Stokes signal from a second pump in the ultraviolet. This spectrally separates the 'preparation' pump from the 'read-out' pump. The low dephasing rate in the ultraviolet permits efficient generation, along the whole fibre length, of anti-Stokes signals from all known Raman-active gas molecules, which is a significant advantage compared to other spectroscopic techniques. The dual-colour pump scheme allows the main detection limit of CARS imposed by the non-resonant background (NRB) to be overcome. It exploits the fact that the NRB is a quasi-instantaneous effect, present only when pump and seed pulses overlap. Although this is also a requirement of Raman excitation, the resulting coherence wave has a lifetime of nanoseconds before it relaxes through intermolecular collisions. Therefore, by appropriately delaying the read-out pump pulse, it is possible to suppress the NRB. Figure 1(a) shows the CARS spectrum for two trace gases, H2 (500 ppm) and CH4 (600 ppm), mixed with the buffer gas N2, measured when the read-out pump overlaps with the Stokes seed. Figure 1 (b) shows the CARS spectrum for 20 ppm of H2 and 350 ppm of CH4, measured when the pump was delayed by 2 ns with respect to the Stokes seed. As can be seen from Fig.1, the dual-colour-pump CARS scheme in SR-PCF reduces the NRB by 120 dB, improving the detection limit by 15 dB and allowing detection of trace gas concentrations as low as 20 ppm with only 20 kW of peak pump power. This novel dual-colour-pump CARS approach has great potential in environmental monitoring and medical applications, offering high sensitivity, short acquisition times (several seconds) and simultaneous multi-species sensing.
关键词： Raman spectroscopy,photonic crystal fibre,dual-colour pump,CARS,trace gas detection
更新于2025-09-11 14:15:04
-
Dual Fabry–Pérot Interferometric Carbon Monoxide Sensor Based on the PANI/Co3O4 Sensitive Membrane-Coated Fibre Tip
摘要： A novel dual Fabry–Pérot (F-P) interferometric carbon monoxide gas sensor based on polyaniline/Co3O4 (PANI/Co3O4) sensing film coated on the optical fibre end face is proposed and fabricated. Its structure is composed of standard single-mode-fibre (SMF), endlessly photonic crystal fibre (EPCF), and PANI/Co3O4 sensing membrane (PCSM). Therefore, they form three F-P reflectors, the reflector between SMF and EPCF, that between EPCF and PCSM, and interface between PCSM and air. So, the dual F-P interferometer is achieved. The results show that in the range of 0–70 ppm, the interference spectra appear red shift with the increasing carbon monoxide concentration. In addition, the high sensitivity of 21.61 pm/ppm, the excellent linear relationship 2 = 0.98476), and high selectivity for carbon monoxide (R are achieved. The response and recovery time are 35 and 84 s, respectively. The sensor has the advantages of high sensitivity, strong selectivity, low cost, and simple structure and is suitable for sensitive detection of trace carbon monoxide gas.
关键词： Photonic Crystal Fibre,Polyaniline,Dual Fabry–Pérot Interferometer,Co3O4,Gas Sensor,Carbon Monoxide
更新于2025-09-09 09:28:46