- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Generation of soliton rain in a passive mode-locked Tm-doped fiber laser at 2???μm
摘要： In this paper, the experimental investigation and theoretical analysis on the soliton rain generated in the Tm-doped ?ber laser have been carried out. On the basis of nonlinear polarization rotation technology, the fundamental and harmonic soliton rain pulses were obtained, the in?uence of net negative dispersion cavity length on the output performances of soliton rain pulse were studied, and the spectral sideband characteristics of soliton rain were numerically analyzed. By comparing the spectra of continuous wave mode-locking and soliton rain states, it can be found that the quasi-periodic modulation exists for the spectral sideband of soliton rain resulted from the complex interaction between the dispersive wave and the soliton wave. The interaction is one of the major factors for the formation of soliton rain. The research results are helpful for the better understanding of the soliton rain dynamics and mechanism in passive mode-locked ?ber lasers.
关键词： Fiber laser,Passively mode-locked,Soliton rain,Tm-doped
更新于2025-09-19 17:13:59
-
Single‐Fiber Laser Ablation in Treating Selected Metastatic Lymph Nodes of Papillary Thyroid Carcinoma and Benign Cold Thyroid Nodules—Preliminary Results
摘要： To evaluate the feasibility and efficacy of single‐fiber laser ablation (LA) under ultrasound guidance and appropriate ablation modes in the treatment of selected metastatic lymph nodes of papillary thyroid carcinoma (PTC) and benign cold thyroid nodules. A total of 18 patients (consisting of 8 patients with 18 metastatic lymph nodes of PTC and 10 patients with 10 benign cold thyroid nodules) each underwent one session of single‐fiber LA under ultrasound guidance. On the basis of the sizes of the nodules, the ablation modes were chosen accordingly. The single‐dot ablation mode was used in the nodules with three orthogonal diameters measuring no greater than 10 mm in diameter, with a dot, a level and an insertion. The double‐dots overlapping ablation mode was used in the nodules with the largest diameters measuring greater than 10 mm (in which the nodules measured no more than 15 mm in diameter and with the other two perpendicular diameters measuring no greater than 10 mm in diameter) with two dots, a level and two insertions. The multiple levels and dots overlapping ablation mode was used in the nodules with the three orthogonal diameters all measuring larger than 10 mm, with multiple dots, levels and insertions. After 12 months of follow‐up in the treated nodules of the metastatic lymph nodes of PTC and benign cold thyroid nodules, the mean baseline volumes decreased from 0.29 ± 0.12 to 0.03 ± 0.03 ml and 3.85 ± 0.64 to 1.1 ± 0.37 ml, respectively, and the mean volume reduction ratios (VRRs), which was calculated as {[(initial volume ?final volume) × 100%]/initial volume}, were 90.3 ± 7.6% and 72 ± 5.8%, respectively. There were six ablative zones that completely disappeared, whereas the ablative zones that still existed presented as scar‐like areas or small hyperechoic areas that were compatible with scar tissue among the 18 malignant nodules at the last follow‐up. Single‐fiber LA under ultrasound guidance, with the appropriate ablation modes, is feasible and effective for the treatment of selected metastatic lymph nodes of PTC and benign cold thyroid nodules. This study suggests that single‐fiber LA may be applied to selected cases with appropriate ablation modes.
关键词： metastatic lymph nodes,ultrasound guidance,papillary thyroid carcinoma,benign cold thyroid nodules,single‐fiber laser ablation
更新于2025-09-19 17:13:59
-
Optical deposition of PtSe2 on fiber end face for Yb-doped mode-locked fiber laser
摘要： In this work, the platinum diselenide (PtSe2), which was prepared by a simple selenization method, was deposited on fiber end face by a special optical deposition method. Compared to the more reported optical deposition methods operating in solution, our method is to complete the optical deposition from a polystyrene/PtSe2 film onto a fiber end face. Then, the optical deposited PtSe2 fiber was used as SA in a fiber laser cavity to generate mode-locking pulses. The central wavelength, pulse width and repetition rate of the mode-locked laser were detected to be 1067.5 nm, 1.9 ns, and 4.45 MHz, respectively. The obtained SNR of the output laser was 45.2 dB, indicating the good stability of the PtSe2-based mode-locked fiber laser. Our results also indicate that more 2D materials could be coated on the fiber end face using this special non-liquid optical deposition method.
关键词： Yb-doped mode-locked fiber laser,Optical deposition,PtSe2 film
更新于2025-09-19 17:13:59
-
Switchable dual-wavelength mode-locked fiber laser using Saganc loop mirror
摘要： We report an all-fiber switchable dual-wavelength mode-locked laser using a Sagnac loop mirror. In this laser, the Sagnac loop mirror acts as a tunable periodic filter, in which the wavelength spacing is determined by the length of the polarization maintaining fiber. With appropriate pump power, the mode-locked fiber laser can operate in both the tunable single-wavelength mode locking regime and the dual-wavelength mode locking regime by properly setting the states of the polarization controllers. In the single-wavelength mode locking regime, the laser achieves continuously tunable wavelength range from ～1551 nm to ～1562 nm. In the dual-wavelength mode locking regime, the laser can emit two stable asynchronous pulse trains with the central wavelengths of 1561.4 nm and 1551.1 nm, respectively. Due to the net negative dispersion of the laser cavity, the mode-locked pulse trains with different central wavelengths have different group velocities leading to a repetition rate difference of ～530 Hz.
关键词： Tunable wavelength,Dual-wavelength,Sagnac loop mirror,Mode-locked fiber laser
更新于2025-09-19 17:13:59
-
Stable generation of orbital angular momentum mode with an all-fiber laser
摘要： In this paper, an all-fiber laser that can generate stable OAM modes with topological charges of ±1 is demonstrated. A ring-core fiber designed in-house is used to reduce the crosstalk between OAM mode and other modes. A ring-core fiber-based long-period fiber grating (LPFG) and a fiber Bragg grating (FBG) are employed to select desired OAM mode. The coupling ratio of LPFG from HE11 mode to OAM mode exceeds 16 dB, and the mode purity of ±1 is demonstrated. The purity of OAM mode is as high as 94.41%. This simple and compact fiber laser can be integrated into fiber-based OAM mode multiplexing optical communication system.
关键词： orbital angular momentum,fiber Bragg grating,ring-core fiber,long-period fiber grating,all-fiber laser
更新于2025-09-16 10:30:52
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Tunable Erbium-Doped Fiber Laser Assisted by a fs-laser Introduced Random Fiber Grating
摘要： A tunable erbium-doped fiber (EDF) laser assisted by a random fiber grating introduced by an fs-laser and a tunable fiber Bragg grating is demonstrated. The tuning range is up to 4.45 nm（1548.04 -1552.49 nm）. Due to the half-opened laser cavity design and the efficient gain from the pumped EDF, the measured threshold pump power is 18 mW, and the slope efficiency is up to 13.2%.
关键词： random fiber grating,tunable laser,Erbium-doped fiber,random fiber laser
更新于2025-09-16 10:30:52
-
[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - Polymer Fiber Lasers
摘要： Polymers doped with laser dyes are promising materials for solid state dye lasers. The development of dye doped polymer optical fibers is presented. Furthermore, experimental results from polymer bulk and fiber lasers based on these optical materials are reported.
关键词： rhodamine B,fiber laser,fiber amplifier,polymer fiber,laser dye
更新于2025-09-16 10:30:52
-
Single-step Laser Plastic Deposition (LPD) using a near-infrared Thulium fiber-laser
摘要： Additive Manufacturing of thermoplastic polymers is typically carried out using techniques such as Selective Laser Sintering (SLS) or Fused Layer Modeling (FLM), both of which require the use of support structures that have to be removed after the production process. The laser welding of thermoplastic polymers using laser sources with a wavelength of around 1 μm and thus also Direct Selective Laser Melting (SLM) in the same wavelength spectrum requires the admixing of additives such as carbon black in order to improve the absorption of laser light within the polymer and hence poses an additional process step that has to be performed. Laser sources like Thulium fiber-lasers with a wavelength of around 2 μm enable the absorber-free welding of thermoplastic polymers and therefore promise to be a new source for the SLM of thermoplastic polymers as well as a possible adaption of the known Laser Metal Deposition (LMD) to plastics, the so called ?Laser Plastic Deposition“ (LPD). In the present paper, the feasibility of a single-step LPD process using irradiation of a 1,94 μm Thulium fiber-laser is investigated through the manual deposition of unfilled and absorber-free polyamide-12 powder on polyamide-6 substrates. Powder material and the created structures are characterized by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). In addition to that, optical microscopy and computer tomography analysis (CT) are carried out and discussed for the created LPD structures. From the experiments, it is to be concluded that a single-step LPD process can be carried out using a 2 μm Thulium fiber-laser.
关键词： Fiber laser,Thulium laser,Polymer cladding,Laser polymer deposition,Laser plastic deposition,Additive manufacturing
更新于2025-09-16 10:30:52
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - More-than-95-line fiber laser based on hybrid gain from the Brillouin effect and erbium-doped fiber
摘要： We demonstrate a multi-wavelength Brillouin fiber laser based on a dual-ring structure to take advantage of the forward and backward Brillouin gain simultaneously with an injected tunable scanning lasing. We used two erbium-doped fiber amplifiers for the amplification of the seed lasing and the operated Brillouin laser. The cascaded stimulated Brillouin effect in the section of dispersion-shifted fiber contributes to the free-oscillation suppression in cavity. When the laser operates at the center wavelength of 1565 nm, the output spectra shows the maximum Brillouin lines of more than 95 with a wavelength spacing of about 0.08 nm under the maximum pump. Through adjusting of the seed wavelength and the tunable filter in cavity, the output spectra can be shifted from 1540 to 1570 nm.
关键词： fiber nonlinear optics,Stimulated Brillouin scattering (SBS),Multi-wavelength fiber laser
更新于2025-09-16 10:30:52
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - All-fiber Passively Mode-locked Femtosecond Laser Based on a Femtosecond Laser Inscribed 45° Tilted Fiber Grating
摘要： A femtosecond erbium-doped fiber laser using a novel 45° tilted fiber grating fabricated by direct femtosecond laser inscription is experimentally demonstrated. The laser generates stable short pulses with pulse width of 752 fs at 1562 nm. The experimental results demonstrate that mode locking is successfully achieved with pulse duration of 752 fs and pulse energy of 2.23 nJ. In particular, this kind of 45° TFG is capable of maintaining the strength and physical integrity of the fiber because it is not necessary to remove the fiber coating during inscription process.
关键词： nonlinear polarization rotation,Erbium-doped fiber laser,tilted fiber grating
更新于2025-09-16 10:30:52