共查询到20条相似文献,搜索用时 78 毫秒
1.
High-concentration Er3+/Yb3+ co-doped silica waveguide amplifiers are numerically analyzed. With optimized rare-earth concentrations the effect of Er3+/Er3+ ion-pairs can be neglected and each Er3+ ion can be assumed to be paired only to the surrounding Yb3+ ions. The rate-equations model includes uniform upconversion mechanisms from 4I13/2 and 4I11/2 erbium levels and an Yb3+ to Er3+ pair-induced energy transfer process. Numerical results demonstrate the possibility of fabricating short- and high-gain integrated optical amplifiers; it is shown that net gain as high as 3 dB/cm can be obtained 相似文献
2.
In experimental and theoretical study of anomalous dispersion in Er3+and Er3+-Yb3+-doped fibers has been developed. Anomalous time delay caused by both absorption and emission at 1.535 μm has been theoretically calculated and experimentally measured. A pump power dependence of anomalous time delay in rare-earth-doped fibers has been theoretically calculated and experimentally investigated. It has been shown that pump power fluctuations lead to propagation time jitter in Er3+-doped fiber amplifiers. The pulse interaction due to refractive index change caused by gain saturation is predicted. It has been shown that for Er 3+-doped fibers with SiO2-GeO2 core composition, the anomalous dispersion per 1-dB gain is twice that of fibers with SiO2-Al2O3 core, which is caused by gain curve form difference. A scheme of mutual compensation of intrinsic fiber dispersion and anomalous dispersion caused by Er3+ in the region 1.532-1.537 μm has been suggested 相似文献
3.
Worhoff K. Bradley J.D.B. Ay F. Geskus D. Blauwendraat T.P. Pollnau M. 《Quantum Electronics, IEEE Journal of》2009,45(5):454-461
A reliable and reproducible deposition process for the fabrication of Al2O3 waveguides with losses as low as 0.1 dB/cm has been developed. The thin films are grown at ~ 5 nm/min deposition rate and exhibit excellent thickness uniformity within 1% over 50times50 mm2 area and no detectable OH- incorporation. For applications of the Al2O3 films in compact, integrated optical devices, a high-quality channel waveguide fabrication process is utilized. Planar and channel propagation losses as low as 0.1 and 0.2 dB/cm, respectively, are demonstrated. For the development of active integrated optical functions, the implementation of rare-earth-ion doping is investigated by cosputtering of erbium during the Al2O3 layer growth. Dopant levels between 0.2-5times1020 cm-3 are studied. At Er3+ concentrations of interest for optical amplification, a lifetime of the 4I13/2 level as long as 7 ms is measured. Gain measurements over 6.4-cm propagation length in a 700-nm-thick Al2O3:Er3+ channel waveguide result in net optical gain over a 41-nm-wide wavelength range between 1526-1567 nm with a maximum of 5.4 dB at 1533 nm. 相似文献
4.
Optical high-temperature sensing using the fluorescence intensity ratio (FIR) technique of green up-conversion emissions at 523 and 546 nm in Er3+-Y3+-codoped Al2O3 was studied in a wide temperature range of 295 K-973 K. The maximum sensitivity and the temperature resolution derived from the FIR technique are approximately 0.0035 K-1 and 0.3 K, respectively, which indicated that Er3+-Y3+-codoped Al2O3 plays an important role for applications in the optical high-temperature sensing. 相似文献
5.
Lester C. Bjarklev A. Rasmussen T. Dinesen P.G. 《Lightwave Technology, Journal of》1995,13(5):740-743
A model for Yb3+-sensitized Er3+-doped silica waveguide amplifiers is described and numerically investigated in the small-signal regime. The amplified spontaneous emission in the ytterbium-band and the quenching process between excited erbium ions are included in the model. For pump wavelengths between 860 and 995 nm, the amplified spontaneous emission in the ytterbium-band is found to reduce both the gain and the optimum length of the amplifier significantly. The achievable gain of the Yb3+-sensitized amplifier is found to be higher than in an Er3+-doped silica waveguide without Yb 3+ (18 dB versus 9 dB for a pump power of 100 mW). However, it is important to optimize the Yb-concentration according to the choice of pump wavelength 相似文献
6.
Short high-concentration Yb3+-sensitized Er3+-doped fiber amplifiers are modeled and numerically investigated in the small-signal domain. Concentration quenching is included with a term quadratic in the concentration of excited Er3+ . We find that for fibers shorter than 1 m, the small-signal gain can be larger for sensitized fibers than for non-sensitized ones (31 dB gain vs. 22 dB at 5 cm). Without concentration quenching (e.g. for long fibers), Yb3+-free amplifiers have a higher small-signal gain. The achievable gain of the sensitized amplifier is independent of the pump laser wavelength, if the Yb-concentration is correspondingly optimized. However, restrictions on allowable Yb-concentrations imply that for a specific pump wavelength, a finite range of amplifiers lengths is suitable 相似文献
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8.
High-concentration Er3+/Yb3+ codoped glass waveguide amplifiers are analyzed by means of a finite-element-based code. Efficient Yb3+ to Er3+ energy transfer is shown to be a useful mechanism to reduce performance degradation due to Er3+ ion-ion interactions. Numerical calculations based on realistic waveguide parameters demonstrate the possibility of achieving high gain with a short device length 相似文献
9.
Messias D.N. Jacinto C. Bell M.J.V. Catunda T. 《Quantum Electronics, IEEE Journal of》2007,43(9):751-757
In this work, we study the thermal and optical properties of ion-doped phosphates glasses using the thermal lens (TL) technique. Three samples were characterized: Nd3+-doped Q-98; Nd3+-doped Q-100; and Yb3+-doped QX. We report multiwavelength TL measurements for a more accuracy determination of the fluorescence quantum efficiency and temperature coefficient of the optical path length change (ds/dT). In Nd-doped glasses, it was carried out using four discrete excitation wavelengths (between 514 and 872 nm) chosen to match with the ion absorption lines. In Yb-doped glass, the spectrum of heat generated along the Yb3+ transition (2 F 5/2rarr2 F 7/2) was obtained. In addition, parameters as thermal diffusivity and conductivity, thermal loading, etc were achieved. The advantages to obtain fluorescence quantum efficiency using the TL technique, mainly in Yb3+ doped materials, which are normally overestimated due to radiation trapping effect, are presented. The accuracy knowledge of these parameters is very important for design of high-power solid-state lasers, since these properties are directly related to the heat generation. 相似文献
10.
We report the first deposition of Er3+-doped aluminum oxide thin-film optical waveguides by plasma-enhanced chemical vapor deposition (PECVD). The aluminum and erbium precursors used for the deposition of the thin films were trimethyl-aluminum and Er tri-chelate of 2,2,6,6-tetramethylheptane-3,5 dione respectively. The samples show broad, room-temperature photoluminescence at λ=1.533 μm. The Er3+ concentration ranged from 0.01-0.2 at%. The full width half maximum (FWHM) of the Er3+ emission spectrum is 55 nm, considerably broader than in silica glass. The radiative lifetime has been measured at 50-mW pump power 相似文献
11.
Barnes W.L. Poole S.B. Townsend J.E. Reekie L. Taylor D.J. Payne D.N. 《Lightwave Technology, Journal of》1989,7(10):1461-1465
Single-mode fiber lasers operating at ~1.57 μm are described. Output powers of >2 mW are reported for laser diode pumped operation. Direct comparison is made between fiber lasers using sensitized erbium (Er3+ and Yb3+) and erbium on its own. The performance of Er3+-Yb3+ fiber lasers is analyzed in more detail as a function of fiber length. Both CW and Q-switched operations are studied and the results obtained demonstrate that practical sources at 1.5 μm are available from diode pumped Er3+ -Yb3+ systems 相似文献
12.
Nykolak G. Becker P.C. Shmulovich J. Wong Y.H. DiGiovanni D.J. Bruce A.J. 《Photonics Technology Letters, IEEE》1993,5(9):1014-1016
We report on the concentration- and pump-dependent lifetimes of the spontaneous emission in Er3+-doped fibers and Er3+ -doped waveguides. In addition, we measure the concentration dependence of the 550-nm fluorescence due to excited state absorption (ESA) 相似文献
13.
In this paper, we report cascaded two-wavelength 853-nm (4 S3/2rarr4I13/2 transition) and 1533-nm (4I13/2rarr4I15/2 transition) lasing from Er3+-doped fluoride fiber pumped at 974 nm. The cavity for cascaded two-wavelength lasing is composed of two fiber ends with 4% Fresnel reflection. Its optical-to-optical efficiency is up to 26.6%. Its effects on C-band fiber amplifiers and green upconversion fiber lasers are discussed. A new way to get high efficiency and low noise C-band amplifier is suggested, i.e., a fluoride-based Er3+-doped fiber amplifier including 853-nm lasing cavity. Our simulated results show that such a new amplifier can enhance the signal gain greatly and break the limit of the saturated gain intensity for a normal amplifier 相似文献
14.
Yujin Chen Yanfu Lin Xinghong Gong Zundu Luo Yidong Huang 《Quantum Electronics, IEEE Journal of》2007,43(10):950-956
An Er:Yb:GdAl3(BO3)4 crystal was grown and room-temperature polarized absorption, emission, and gain spectra were investigated. Fluorescence decay curves of Er3+ at 1530 nm and Yb3+ at 1040 nm in the crystal were measured. Efficient laser operation of Er:Yb:GdAl3(BO3)4 crystal at 1.5-1.6 mum was realized. Quasi-continuous-wave output powers of 1.8 W with slope efficiency of 19% and 0.78 W with slope efficiency of 14% were achieved in diode-pumped c-cut and c-cut and a-cut crystals, respectively. The output spectrum and polarization of Er:Yb:GdAl3(BO3)4 laser were also investigated. 相似文献
15.
Ytterbium-doped sodium phospho-tellurite glasses are made with different P2O5:TeO2 ratio, and Yb3+ concentrations. Physical properties of the new Yb hosts are favorable for laser applications. The glasses show high absorption and emission cross sections and higher lifetime of Yb3+:2F5/2rarr2F7/2 transition. The emission cross sections are calculated using two different methods and compared. The laser parameters of these Yb3+ -doped glasses are better than many reported glasses and crystals making them potential to fabricate high power laser and broadband optical amplifier in the wavelength region around ~1 mum 相似文献
16.
A biconical taper amplifier utilizing an Er3+-doped cladding fiber is discussed. A maximum gain of 0.6 dB in a 2.4-Gb/s optical transmission experiment was obtained with a taper about 40 mm long. This result shows the potential of a new structure for Er3+ -doped coupling and amplifying components 相似文献
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18.
Minelly J.D. Barnes W.L. Laming R.I. Morkel P.R. Townsend J.E. Grubb S.G. Payne D.N. 《Photonics Technology Letters, IEEE》1993,5(3):301-303
Single-mode double-clad Er3+/Yb3+ co-doped fibers are shown to be suitable for diode array pumping at around 960 nm. A fiber laser with 96-W output power at 1.53 μm and a power amplifier exhibiting a small signal gain of 24 dB and a saturated output power of +17 dBm are reported 相似文献
19.
Highly efficient amplification of ultrashort optical pulses is demonstrated with a two-stage Er3+-doped optical fiber amplifier that includes an optical gate to efficiently reduce amplified spontaneous emission (ASE) generated from the first Er3+-doped fiber. A gain of 49 dB, an amplified peak power 0f 105 W, and 1.05 nJ pulse energy are achieved for 2-Mb/s, 10-ps pulses at a total pumping power of 90 mW from 1.48-μm LDs 相似文献
20.
Transient gratings with R>96% at 1526 nm have been observed in Er3+/Yb3+-doped phosphosilicate optical fibres holographically processed with 193 nm light. These arise primarily from the index change associated with population inversion of the Er3+ ions 相似文献