- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Mode-locking in Er-doped fiber laser with reduced graphene oxide on a side-polished fiber as saturable absorber
摘要： In this work, the generation of highly stable mode-locked pulses from a side-polished fiber (SPF) embedded with graphene oxide (rGO) nanoparticles (NPs) is proposed and demonstrated. The rGO NPs are obtained from a graphene oxide solution prepared using Hummer’s technique, before being reduced by a hydrothermal route. The rGO NPs, suspended in the form of a solution, are then drop-casted onto the SPF. The SPF is fabricated by polishing away the cladding layer of a single-mode fiber section, leaving the core exposed and allowing the evanescent field of the signal propagating through the fiber to interact directly with the NPs. The SPF is integrated into an erbium doped fiber laser (EDFL) cavity, and the strong nonlinear optical response and spectral filtering by the rGO NPs as well as total anomalous dispersion of the laser cavity generates highly stable soliton mode-locked pulses with visible Kelly’s sidebands at 1544.02 nm. The output pulses have a pulse repetition rate of 16.79 MHz and pulse duration of 1.17 ps throughout the mode-locking operation range of 64.44–280.5 mW. The rGO NP coated SPF in this work demonstrates the viability and performance of the SPF for mode-locked pulse generation via evanescent field interactions.
关键词： Side polished fiber,Reduced graphene oxide,Mode-locked fiber laser,Saturable absorber
更新于2025-11-28 14:23:57
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Self-generating Brillouin fiber laser using highly nonlinear hafnium bismuth erbium-doped fiber
摘要： A compact Brillouin fiber laser (BFL) utilizing a newly developed hafnium bismuth erbium-doped fiber (HB-EDF), which functions as both the Brillouin and linear gain media, is realized in the absence of Brillouin pump. It is achieved by the self-Brillouin generation from a 0.2 m length of HB-EDF with high nonlinearity in a laser cavity. The self-generating BFL was obtained in both ring and linear laser cavities. Compared to the ring cavity, the BFL in the linear cavity produced more Brillouin stokes at a lower pump threshold. In the experiment, an eight-line comb with average spacing of 0.087 nm was generated at the HB-EDF pump power of 75.27 mW. This compact BFL has total cavity length of less than 0.5 m, and thus, this is the shortest gain medium reported.
关键词： hafnium bismuth erbium-doped fiber,self-generating Brillouin fiber laser,stimulated Brillouin scattering
更新于2025-11-28 14:23:57
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Temperature fiber sensor based on single longitudinal mode fiber laser in 2?μm band with Sagnac interferometer
摘要： A single longitudinal mode (SLM) ?ber laser with a ring cavity based on Sagnac interferometer (SI) for temperature sensing in the 2-μm band is proposed and demonstrated. The simulation and experimental results show that the transmission spectrum of the SI ?lter is sensitive to temperature change. Based on this distinguishing feature, the correlation between the laser wavelength drift and temperature variation can be established. Experimental results show that the proposed laser operates stably at the resonant wavelength of 1988.21 nm and the optical signal-to-noise ratio is approximately 55 dB at ambient temperature. Through continuous measurement for 100 min, the ?uctuation of the output laser power is lower than 0.74 dB, and the resonant wavelength shift is less than the minimum resolution of the spectrometer of 0.05 nm. This indicates that it has good stability for a certain period of time. At the same time, the laser operates stably in SLM state. A temperature sensitivity of 2.09 nm/°C is obtained in experiment. Notably, the proposed ?ber laser sensor possesses the merits including high sensitivity, low cost and simple structure, which are bene?cial to its practical application.
关键词： Fiber optics sensors,Temperature measurement,Sagnac interferometer,Fiber laser,2-μm band
更新于2025-11-28 14:23:57
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Widely Wavelength-tunable Mode-locked Fiber Laser Based on a 45° Tilted Fiber Grating and Polarization Maintaining Fiber
摘要： We present a passively mode-locked Erbium-doped fiber laser with tunable parameters including central wavelength, 3dB bandwidth and pulse duration. The mode-locking mechanism of the laser is realized by using single-walled carbon nanotubes polyvinyl alcohol (SWCNTs-PVA) composite film as saturable absorber. The tunable operation is implemented via a fiber birefringence filter consisting of a polarization maintaining (PM) fiber and a Brewster fiber grating. The laser achieves a maximum spectral tuning range of 36 nm with 8 cm PM fiber. The maximum spectral width variation of 5.19 nm is acquired when the PM fiber is 12 cm. Simultaneously, the spectral widths of pulses at different central wavelengths are also adjustable. Furthermore, the total cavity length is 8.28 m, which is the shortest cavity length to obtain such wide tuning range in an Erbium-doped fiber laser based on SWCNTs.
关键词： Passively mode-locked fiber laser,spectral width,wavelength-tunable,pulse width,tilted fiber grating
更新于2025-11-28 14:23:57
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Mega-Hertz repetition rate broadband nano-second pulses from an actively mode-locked Yb-fiber laser
摘要： This work demonstrates an actively mode-locked all-normal dispersion Yb-fiber ring laser, delivering pulses of few nano-seconds (ns) to sub-ns duration at a 4 MHz repetition rate. Employing a filterless cavity architecture and different, long-length intra-cavity nonlinear fibers; a broadband output spectrum in the 1060–1140 nm wavelength region was obtained. With an increasing pump power, the pulse width reduced along with the appearence of new pulses, resulting into a muti-pulsing output. For a fixed pump power, the number of pulses and the amount of spectral broadening varied for different non-linear fibers. In the multi-pulsing state, the pulses were found to be located seperately in both time and wavelength, where Raman stokes corresponding to individual pulses could also be observed. The maximum output pulse energy achieved in a single pulse state was around 8.7 nJ, which increased to 14.5 nJ in a multi-pulse state. To the best of the authors’ knowledge, this is the first demonstration of a filterless active mode-locked fiber ring laser producing high-repetition rate broadband nano-second pulses in single and multi-pulse states at 1 μm.
关键词： broadband laser,fiber laser,actively mode-locked laser,nano-second pulses
更新于2025-11-28 14:23:57
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Nanotube mode-locked, wavelength and pulsewidth tunable thulium fiber laser
摘要： Mode-locked oscillators with highly tunable output characteristics are desirable for a range of applications. Here, with a custom-made tunable filter, we demonstrate a carbon nanotube (CNT) mode-locked thulium fiber laser with widely tunable wavelength, spectral bandwidth, and pulse duration. The demonstrated laser’s wavelength tuning range reached 300 nm (from 1733 nm to 2033 nm), which is the widest-ever that was reported for rare-earth ion doped fiber oscillators in the near-infrared. At each wavelength, the pulse duration can be regulated by changing the filter’s bandwidth. For example, at ~1902 nm, the pulse duration can be adjusted from 0.9 ps to 6.4 ps (the corresponding output spectral bandwidth from 4.3 nm to 0.6 nm). Furthermore, we experimentally and numerically study the spectral evolution of the mode-locked laser in presence of a tunable filter, a topic that has not been thoroughly investigated for thulium-doped fiber lasers. The detailed dynamical change of the mode-locked spectra is presented and we observed gradual suppression of the Kelly sidebands as the filter’s bandwidth is reduced. Further, using the polarization-maintaiing (PM) cavity ensures that the laser is stable and the output laser’s polarization extinction ratio is measured to exceed 20 dB.
关键词： thulium fiber laser,spectral bandwidth,polarization-maintaiing cavity,Kelly sidebands,tunable wavelength,pulse duration,Mode-locked oscillators,carbon nanotube
更新于2025-11-28 14:23:57
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Mid infrared gas spectroscopy using efficient fiber laser driven photonic chip-based supercontinuum
摘要： Directly accessing the middle infrared, the molecular functional group spectral region, via supercontinuum generation processes based on turn-key fiber lasers offers the undeniable advantage of simplicity and robustness. Recently, the assessment of the coherence of the mid-IR dispersive wave in silicon nitride (Si3N4) waveguides, pumped at telecom wavelength, established an important first step towards mid-IR frequency comb generation based on such compact systems. Yet, the spectral reach and efficiency still fall short for practical implementation. Here, we experimentally demonstrate that large cross-section Si3N4 waveguides pumped with 2 μm fs-fiber laser can reach the important spectroscopic spectral region in the 3–4 μm range, with up to 35% power conversion and milliwatt-level output powers. As a proof of principle, we use this source for detection of C2H2 by absorption spectroscopy. Such result makes these sources suitable candidate for compact, chip-integrated spectroscopic and sensing applications.
关键词： mid infrared,photonic chip,gas spectroscopy,supercontinuum generation,fiber laser
更新于2025-11-28 14:23:57
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Multi-wavelength oscillating and transverse mode switching in an all few-mode fiber laser based on polarization manipulation
摘要： We have proved the polarization dependence of the fiber Bragg grating (FBG), and demonstrated an all few-mode fiber laser that can realize multi-wavelength oscillation and switchable transverse modes simultaneously based on the polarization dependence of FBG. In this fiber laser, single-, dual- and triple-wavelength oscillation can be realized by merely adjusting the polarization controller inside the cavity. Three output transverse modes including fundamental mode, second-order mode, and hybrid modes can be switched as the laser operates at three different single-wavelengths correspondingly. In addition, azimuthally and radially polarized beams can be easily generated. This all few-mode fiber laser scheme may play a more significant role in wavelength division multiplexed (WDM) systems, mode division multiplexed (MDM) systems, sensing, and so on.
关键词： Polarization dependence,Multi-wavelength,Transverse mode,Fiber laser
更新于2025-11-28 14:23:57
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100?GHz free spectral range-tunable multi-wavelength fiber laser using single–multi–single mode fiber interferometer
摘要： Six single–multi–single (SMS) mode fiber-based Mach–Zehnder Interferometers (MZI) with different spooling radii are demonstrated as spatial mode filtering elements for multi-wavelength laser generation. Free spectral range (FSR) tuning of the multi-wavelength output generated is realized by alternating between the six MZIs, which have different macro-bending losses. Additional FSR tuning is also realized by changing the spooling radius of the two-mode step index fiber section within the MZI setups from 80 mm to 30 mm, giving an FSR tuning range of 0.89–0.99 nm. All generated multi-wavelength outputs show high stability over a test period of 100 min. The proposed multi-wavelength lasers are highly suitable for various microwave photonics applications the field of such as microwave signal source generation and microwave photonic filtering.
关键词： free spectral range tuning,Mach–Zehnder Interferometer,microwave photonics,multi-wavelength fiber laser
更新于2025-11-28 14:23:57
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Demonstration of linewidth measurement based on phase noise analysis for a single frequency fiber laser in the 2 <i>μ</i> m band
摘要： Linewidth measurement based on phase noise analysis using a 3 × 3 coupler has been applied in the 1550 nm band. One of the obvious advantages of this method compared with the common delayed self-heterodyne method is the low loss caused by the short delay line used. Taking full advantage of this particular characteristic, the linewidth of the single frequency (SF) fiber laser in the 2 μm band can also be measured. However, a specifically experimental demonstration of this method in the 2 μm band is absent to date. In this paper, a high-performance SF thulium-doped fiber laser (TDFL) was proposed and employed for the demonstration. The TDFL operates at the center wavelength of 1942.03 nm with high stability. By means of the phase noise analysis-based linewidth measurement system with a fiber delay line of only 50 m, the linewidth of the proposed TDFL is successfully measured. When the measuring time is 0.001 s, the linewidth is ~47 kHz. Furthermore, the noise characteristics of the SF laser were simultaneously studied by this method.
关键词： 2 μm band,phase noise,single frequency fiber laser,linewidth measurement
更新于2025-11-28 14:23:57