共查询到20条相似文献,搜索用时 62 毫秒
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研究了作者研制的Cr~(3+):LGT晶体的室温吸收和荧光光谱,用比较简捷的方法进行了能级、晶场强度和跃迁截面的计算分析,从光谱学观点可以认为这种晶体是一种较有潜力的终端声子可调谐激光材料。 相似文献
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采用助熔剂法生长了Ho3+,YB3+共掺的Ho3+,YB3+YA13(BO3)4(Ho,YBYAB)晶体,测量了晶体的室温吸收谱,进而根据Judd-Ofelt(J-O)理论计算了Ho3+在Ho,YBYAB晶体中的强度参数、自发辐射几率和积分发射截面等参数,得到强度参数为Ω2=1.50639×10-18 cm2、Ω4=4.86489×10-19 cm2和Ω6=1.40248×10-19 Cm2.研究了晶体的荧光特性,并在976 nm激光泵浦下得到了上转换绿色荧光. 相似文献
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《电子元件与材料》2017,(2):6-9
研究了传统固相反应法制备所得xCa_(0.5)Nd_(0.5)(Mn_(0.7)Fe_(0.3))O_3-(1–x)Ca_(0.61)Nd_(0.26)TiO_3(0.1≤x≤0.25,CNMFT_x)多晶陶瓷相组成、显微结构、烧结性能与微波介电性能之间的影响关系。X射线衍射研究表明,在研究组分范围内CNMFT_x样品均为单一正交钙钛矿结构;当烧结条件为1 400℃/4 h,x=0.1~0.2时,Fe~(3+)/Mn~(3+,4+)替代Ca_(0.61)Nd_(0.26)TiO_3中Ti~(4+)后,相对介电常数(εr为88.5~77.5)、品质因子(Q·f为7 010~9 370 GHz)和谐振频率温度系数(τf为207.4×10~(–6)/℃~149.1×10~(–6)/℃)逐渐降低,而当x=0.25时,εr(73.4)与τf值(119.6×10~(–6)/℃)仍按规律降低,虽然此时样品晶粒尺寸更为均匀,但Q·f值(5 100 GHz)降幅增加。因此,对于ABO3型钙钛矿结构的微波介质陶瓷,当具有铁磁效应离子的添加量较小时,微波介电性能的变化符合预期规律;但当置换量达到一定比例时,铁磁性增加,导电性增强,巨磁电阻效应减小,致使微波陶瓷介电损耗增加。 相似文献
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Gd_xY_(1-x)Ca_4O(BO_3)_3晶体非临界相位匹配产生1064nm三次谐波 总被引:1,自引:0,他引:1
通过研究生长不同Gd离子和Y离子配比组份的GdxY1 -xCa4 O(BO3) 3晶体 ,得到了室温下可以实现非临界相位匹配产生 10 64nm三次谐波的新型非线性光学晶体Gd0 .37Y0 .6 3Ca4 O(BO3) 3。报道了GdxY1 -xCa4 O(BO3) 3晶体实现10 64nm三次谐波的相位匹配角。用电光调Q的Nd∶YAG激光器对一块长 11mm ,Y 轴切割的Gd0 .37Y0 .6 3Ca4 O(BO3) 3晶体进行了转换效率的测量 ,其结果为 14 7%。 相似文献
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以PbO作助熔剂采用高温溶液法生长出Pb(Mg1/3Nb2/3)O3弛豫铁电晶体,利用X线衍射仪(XRD)和扫描电子显微镜(SEM)分析了晶体相结构和生长形貌。研究结果表明,采用高温溶液法生长出纯钙钛矿相结构的Pb(Mg1/3Nb2/3)O3弛豫铁电晶体,晶体多为淡黄色,较小的呈赝立方形态,较大晶体逐渐趋于不规则形态,最大尺寸达4mm×4mm×3mm。晶体中存在位错蚀坑和PbO包裹等生长缺陷,生长过程中的温度波动和成分起伏等因素导致这些缺陷的出现。晶体{100}面生长速率最慢能成为热力学上稳定存在的自然显露晶面,晶体的生长机制为二维成核层状生长。 相似文献
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新型激光晶体Gd_3(In,Ga)_2Ga_3O_(12):Cr~(3+)的发光 总被引:3,自引:0,他引:3
本文首次报道了一种用熔盐法生长的新型终端声子激光晶体Gd_3(In,Ga)_2Ga_2O_(12):Cr~(3+)的光谱特性。根据室温吸收谱及荧光谱确定了该晶体的若干主要光谱参数。 相似文献
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采用化学共沉淀法合成YAG∶Eu3+红色荧光粉,利用XRD、荧光光谱和激光粒度仪等表征荧光粉晶体结构、光致发光、粒径分布等。结果表明,当煅烧温度为1000℃时,荧光粉YAG晶相趋于稳定,无中间相的形成,合成温度比传统高温固相法降低近500℃;随着煅烧温度升高,荧光粉光致发光峰强度增大,但峰值波长并不随煅烧温度升高而发生移动;前驱体中添加表面活性剂PEG后,荧光粉粒径为1.3μm左右,且粒径分布范围窄;助熔剂NaF能够显著提高荧光粉的光致发光强度,但过量则会出现浓度猝灭,其最佳添加量为4%。 相似文献
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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
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Azkargorta J. Iparraguirre I. Balda R. Fernandez J. 《Quantum Electronics, IEEE Journal of》1997,33(3):474-482
Energy transfer between Cr3+ and Nd3+ ions has been investigated in the 4.2-300-K temperature range by using steady-state and site-selective time-resolved laser spectroscopy. Radiative and nonradiative energy transfer has been studied from the time-resolved emission spectra and the donor fluorescence decays. The transfer efficiency was calculated as a function of temperature by using the Cr3+ lifetimes of the single doped and co-doped samples. Laser experiments were carried out in a diffusive cavity by pumping a co-doped rod 54 mm long and 5 mm in diameter with xenon flashlamps. The laser spectral emission shows a complex structure which varies as a function of pump energy. The temporal evolution of the laser spectrum is discussed in terms of a simple four-level spectral rate-equation laser model which takes into account the existence of two main broad Nd3+ site distributions with a large spectral overlap 相似文献
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Payne S.A. Chase L.L. Smith L.K. Kway W.L. Krupke W.F. 《Quantum Electronics, IEEE Journal of》1992,28(11):2619-2630
The absorption and emission cross sections of the transition between the ground spin-orbit multiplet and the lowest excited multiplet were measured for Er3+, Tm3+, and Ho3+ ions in a variety of crystalline hosts. The materials that were investigated include LiYF4, BaY2F8, Y 3Al5O12, LaF3, KCaF3 , YAlO3, and La2Be2O5. The absolute magnitudes of the emission cross sections were determined from the absorption spectra, with the aid of the principle of reciprocity. The calculated radiative emission lifetimes derived from these measured cross sections agree well with the measured emission decay times for most materials. The potential use of these rare-earth-doped materials in pulsed laser applications requires that the ground state exhibit adequate splitting to minimize the detrimental effects of the ground state thermal population, and also that the emission cross section be sufficiently large to permit efficient extraction energy. The systems based on Ho3+ in the eightfold coordinated sites of LiYF4, BaY2F8, and Y3Al5O12 appear to be the most promising 相似文献
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Laser action has been observed for the following rare-earth ions in YAlO3 :Ho3+(sensitized with Er3+and Tm3+), Er3+, and Tm3+(sensitized with Er3+) at wavelengths of 2.123, 0.851, and 1.861 μm, respectively. Measurements of spectroscopic properties, fluorescence kinetics, and laser performance of these ions in YAlO3 are reported. 相似文献
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磷酸盐玻璃中稀土离子Ce~(3 )、Tb~(3 )、Er~(3 )和Tm~(3 )的能量转移和敏化过程的研究 总被引:2,自引:1,他引:1
本文报道了磷酸盐玻璃中Tb~(3 )和Ce~(3 )的浓度猝灭效应。在KrF激光(248毫微米,10毫微秒)激发下,测出磷酸盐玻璃中不同浓度Ce~(3 )或Tb~(3 )离子的荧光寿命。着重讨论了磷酸盐玻璃中Ce~(3 )→Tb~(3 )、Er~(3 )和Tm~(3 )的能量转移和敏化过程。 相似文献
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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
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Ag纳米颗粒对Er3+/Tm3+/Yb3+共掺铋锗酸盐玻璃上转换发光特性的影响 总被引:1,自引:1,他引:0
采用传统熔融淬冷法制备了系列Er3+/Tm 3+/Yb3+共掺复合Ag纳米颗粒的铋锗酸盐玻璃样品。从吸收光谱中 确定了Ag纳米颗粒表面等离子体共振(SPR)峰位于545nm附近;透射 电镜(TEM)图像中观察到均匀分布的Ag纳米颗粒,尺寸 约为6~18nm。研究了纳米Ag含量对Er3+/Tm3+ 共掺复合Ag纳米颗粒铋锗酸盐玻璃上转换发光特性的影响,结果表 明,Tm3+离子472nm处的上转换蓝光、Er3+离子525nm处的上转换绿光、543nm处的上转换 绿光和661nm处的上转换红光发光强度在AgCl含量的质量百分数为 1%时达到最大值,与未掺杂AgCl的基质玻璃相比,分别提高了约3.2、3.8、5.4倍。 相似文献
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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