- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Enhancing Photovoltaic Performance of GaAs Single-Junction Solar Cells by Applying a Spectral Conversion Layer Containing Eu-Doped and Yb/Er-Doped Phosphors
摘要： In this study, we examined e?orts to increase the photovoltaic performance of GaAs single-junction solar cells using spectral conversion layers, respectively, composed of europium-doped (Eu-doped) phosphors, ytterbium/erbium-doped (Yb/Er-doped) phosphors, and a combination of Eu-doped and Yb/Er-doped phosphors. Spin-on ?lm deposition was used to apply the conversion layers, all of which had a total phosphor concentration of 3 wt%. The chemical compositions of the phosphors were examined by energy-dispersive X-ray spectroscopy. The ?uorescence emissions of the phosphors were con?rmed by using photoluminescence measurements. Under laser diode excitation at 405 nm, we observed green luminescent downshift (LDS) emissions by Eu-doped phosphors at wavelengths of 479 nm to 557 nm, and under excitation at 980 nm, we observed red up-conversion (UC) emissions by Yb/Er-doped phosphors at wavelengths of 647 nm to 672 nm. The spectral conversion layers were characterized in terms of optical re?ectance, external quantum e?ciency, and photovoltaic current and voltage under AM 1.5 G simulations. The conversion e?ciency of the cell combining Eu-doped and Yb/Er-doped phosphors (23.84%) exceeded that of the cell coated with Yb/Er-doped phosphors (23.72%), the cell coated with Eu-doped phosphors (23.19%), and the cell coated without phosphors (22.91%).
关键词： ytterbium/erbium-doped (Yb/Er-doped),europium-doped (Eu-doped),up-conversion,phosphors,GaAs solar cell,luminescent downshift
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 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) - Erbium-Doped Fiber Dual-Wavelength Mode Locked Laser With Few-Layer NiPS <sub/>3</sub>
摘要： In recent years, as optical modulator materials, two-dimensional (2D) materials attracted much attention for mode-locking pulse generating. However, some 2D materials like graphene have no band gap, leading to weak light absorption, while other 2D materials such as black phosphorus have poor stability, which may affect the continuity of the laser. As a kind of new 2D ternary layered material, NiPS3 can exhibit more novel electrical, optical and magnetic properties compared with those unary and binary 2D layered materials because of higher chemical diversity and structural complexity. In this work, we demonstrated proposed dual-wavelength mode-locked erbium-doped all-fiber laser (EDFL) by utilizing the few-layer NiPS3 as the saturable absorber (SA). The total length of the laser cavity was about 40 m with a 20m-long single mode fiber integrated. The SA was integrated into the EDFL by sandwiching it between two fiber ferrules. In stable dual-wavelength mode-locked operation, the pulse was generated at 1563.8 nm and 1564.5 nm with a repetition rate of 5.117 MHz with signal-to-noise ratio (SNR) of 51.70 dB. Meanwhile, the highest peak power of 7.46 nJ corresponded to the maximum output power of 1.54 mW. Our experiments validated that the few-layer NiPS3 can be utilized as a SA to generate stable all-fiber pulsed laser the fabrication of NiPS3 in this work would allow the generation of mode-locked pulse, which expands two-dimensional (2D) materials application in ultrafast pulse generation.
关键词： Mode-locked,Erbium-doped fiber,NiPS3
更新于2025-09-16 10:30:52
-
Tunable multiwavelength erbium-doped fiber laser based on BPQDs packaged by poly tetra fluoroethylene and two segments of PMF
摘要： Two types of tunable and stable multiwavelength erbium-doped fiber lasers(MWEDFLs) are proposed and experimentally demonstrated, which are based on novel poly tetra fluoroethylene packaging device of black phosphorus quantum dots (PTFEPD-BPQDs) and two sections of polarization maintaining fiber(PMF) in cascade/in parallel. The novel fabrication process uses silica capillaries and PTFE to package BPQDs. The PTFEPD-BPQDs has the function of suppressing the mode competition and stabilizing the multiwavelength output. The channel space and wavelength number of the two types of tunable MWEDFLs can be tuned by adjusting polarization controllers(PCs). In the experiments, for the unpackaged BPQDs device, BPQDs will degrade and lose its function within 48 h, while for the PTFEPD-BPQDs, BPQDs can keep its function for more than 3 weeks. By adjusting the PC, in the cascaded structure, the multiwavelength channel spacing can be tuned among nearly 1.98, 0.67 and 0.43 nm, and the number of multiwavelength output is 4, 9 and 13, respectively.
关键词： Tunable,Two sections of polarization maintaining fiber,Multiwavelength erbium-doped fiber laser,Black phosphorus quantum dots
更新于2025-09-16 10:30:52
-
Widely 70-nm wavelength tunability single-frequency erbium laser utilizing multiple-ring architecture
摘要： In this paper, to accomplish the broadly wavelength tunability and single-longitudinal-mode (SLM) operation of erbium-doped fiber (EDF) based laser, the multiple-ring structure is designed and executed. The output power of ?7.3 to 5.1 dBm and optical signal to noise ratio (OSNR) of 31.5 to 36.7 dB/0.06 nm are obtained for the proposed EDF laser over the tuning range of 1520.0–1590.0 nm based on the C-band EDF gain medium. In addition, the Lorentzian linewidth of 14.9 to 20.4 kHz is also attained.
关键词： Wavelength-tunability,Erbium-doped fiber,Single-longitudinal-mode (SLM),Fiber laser,Multiple-ring
更新于2025-09-16 10:30:52
-
Stable Single-Longitudinal-Mode Fiber Laser With Ultra-Narrow Linewidth Based on Convex-Shaped Fiber Ring and Sagnac Loop
摘要： In this investigation, a convex-shaped ?ber ring (CSFR)-based single-longitudinal-mode (SLM) erbium-doped ?ber laser (EDFL) is proposed and experimentally veri?ed. The CSFR, composed of only two optical couplers and forming a double-ring architecture, is employed to serve as a high quality mode ?lter to eliminate the dense longitudinal modes of the EDFL. The unpumped erbium-doped ?ber in the Sagnac loop is utilized to produce the ultra-narrowband auto-tracking ?lter effect as a saturable absorber to guarantee the SLM out. The experimental results show that the linewidth of the proposed EDFL is 840 Hz with a high optical signal to noise ratio of 63 dB. In addition, the stability of the EDFL with the maximum output power ?uctuation of 0.01 dB and the maximum central wavelength variation of 0.01 nm, in both the short-term and the long-term observations. Hence, we obtained a SLM EDFL with extremely high stability, ultra-narrow linewidth and high optical signal to noise ratio (OSNR).
关键词： saturable absorber,Single longitudinal mode (SLM),erbium-doped ?ber laser (EDFL)
更新于2025-09-16 10:30:52
-
Using erbium-doped yttrium aluminum garnet laser irradiation in different energy output levels versus ultrasonic in removal of root canal filling materials in endodontic retreatment
摘要： Objectives: The objective of this study was to evaluate the efficacy of erbium?doped yttrium aluminum garnet (Er:YAG) laser irradiation in different energy outputs versus ultrasonic in gutta-percha removal during the endodontic retreatment. Materials and Methods: A total of 21 extracted human lower premolars were divided into three groups (n = 7). Following the standardized preparation of the root canals with Wave One Rotary system and obturation with gutta-percha: Group I was treated with ultrasonic, Group II by Er:YAG laser with 40 mJ/Pulse, and Group III by Er:YAG laser with 50 mJ/Pulse for the removal of gutta?percha from the canals. Two extra teeth were treated by Er:YAG laser with 135 mJ/Pulse as control group. For all groups, time for gutta-percha removal was recorded. Samples were then splited into two halves and tested by scanning electron microscope and stereomicroscopic evaluation under different magnification power to observe the efficacy of each method used in the removal of gutta-percha. Results: Statistical analysis of Kruskal–Wallis suggested that there are significant difference between the groups in relation to removal time (P < 0.05) and 2 × 2 Mann–Whitney U-test among the groups revealed that there is no significant difference between 40 and 50 mJ laser outputs (P > 0.05), but ultrasonic versus 40 and/or 50 mJ laser outputs were significantly different (P < 0.05). Conclusions: Er:YAG laser beam was not so efficient when compared to ultrasonic to reach the deeper parts of the canals as it was asserted, thermal side effects and burning damages were observed on the root canal dentinal walls. Moreover, the delivery system was not flexible enough to compensate the curvature of the canal system even though we used more straight canals as the sample ones as well as more time-consuming than the ultrasonic and more clinical time, rendering it to be less efficient in the removal of the obturation material during endodontic retreatment procedures.
关键词： gutta-percha removal,erbium-doped yttrium aluminum garnet lasers,Endodontics,retreatment,lasers
更新于2025-09-16 10:30:52
-
Malpositioned canine treatment with autotransplantation and laser
摘要： Children and young adults often have tooth loss due to congenital tooth deficiency, trauma, or caries. Autotransplantation has many benefits. The transplanted tooth can be moved orthodontically, maintains alveolar bone growth potential during eruption, and functional periodontal ligament function also permits tooth eruption, allows the defected areas to be filled with the bones; gingival contour is much more successful than the one obtained with prosthesis. In this paper, treatment steps and follow?up results of autotransplantation case supported with biostimulation are mentioned. A 14?year?old female patient was admitted to the clinic with a complaint of decayed tooth 53 and malposed tooth 13. Mobile primary tooth was pulled out, and the socket was shaped with surgical drills. By performing transplantation of ectopic canine, splint was applied with steel wire and composite. Diode laser was used to provide deep disinfection of canals. The patient underwent low-dose laser therapy for biostimulation immediately after these procedures. We did not encounter any ankylosis, root resorption, periodontal, or functional problems in our evaluation with computed tomography after 3 years follow-up of the patient.
关键词： erbium,biostimulation,Autotransplantation,diode laser,chromium:yttrium-scandium-gallium-garnet
更新于2025-09-16 10:30:52
-
Tunable passively Q-switched ultranarrow linewidth erbium-doped fiber laser
摘要： A tunable passively Q-switched erbium-doped fiber laser with ultranarrow linewidth is proposed and demonstrated. With the single wall carbon nanotubes (SWCNTs) as the passive Q-switch, the ultranarrow linewidth laser operation is realized based on spectral filtering effect using an ultranarrow tunable bandpass filter (UNTBF). The Q-switched laser spectrum is tunable from 1525 to 1561 nm, covering a wavelength range of 36 nm. At 1545 nm, the highest repetition rate of ~ 38 kHz and the lowest pulse width of 1.15 μs are obtained, with the corresponding pulse energy of approximately 0.18 nJ. The linewidth measurement using self-heterodyne technique yields a linewidth value of 17.5 kHz, which may be the narrowest linewidth for a Q-switched fiber laser to the best of our knowledge.
关键词： Ultra-narrow linewidth,passively Q-switched,tunable wavelength,erbium-doped fiber laser
更新于2025-09-16 10:30:52
-
Holmium oxide thin film as a saturable absorber for generating Q-switched and mode-locked erbium-doped fiber lasers
摘要： We demonstrated a new type of transition metal oxide (TMO) material, Holmium oxide (Ho2O3) polymer ?lm SA for compact passively Q-switched and mode-locked erbium-doped ?ber laser (EDFL) generations. The ?lm SA has a thickness of ~40 μm and modulation depth of ~45%. It was fabricated by embedding Ho2O3 nanoparticles into PVA polymer solution. The Q-switched laser operated stably at a center wavelength of 1563 nm within a pump power range of 45–97 mW. The maximum Q-switching pulse repetition rate and the narrowest attainable pulse width were 115.8 kHz and 0.64 μs, respectively; while, the maximum pulse energy was obtained as 129.36 nJ. On the other hand, the mode-locked EDFL emerged stably within a pump power range of 62–180 mW at a center wavelength of 1565.4 nm. The repetition rate was 17.1 MHz, while the pulse width was 650 fs. Additionally, the maximum output power was measured as 9.01 mW; while, the corresponding maximum pulse energy was obtained as 0.524 nJ. This Ho2O3 ?lm SA o?ers simplicity and reliability in the design of compact and portable ?ber pulsed laser generators particularly in the 1.55-μm regime.
关键词： Mode-locked,Saturable absorber,Q-switched,Ho2O3,ERBIUM-doped ?ber laser
更新于2025-09-16 10:30:52