共查询到20条相似文献,搜索用时 312 毫秒
1.
采用高温熔融法制备了不同Er3+掺量的硼硅酸盐玻璃。测量和分析了玻璃样品的光密度和吸收光谱,并用最小二乘法拟合了实验与理论吸收谱线。应用Judd-Ofelt理论计算了光谱参数Ωλ(λ=2,4,6)和Er3+的振子强度,计算了拟合过程中的均方根偏差(δ),并讨论了Er3+浓度对对光密度和Ωλ参数的影响。分析结果表明:当Er2O3含量为21mol%时,玻璃在达到了较高的光密度(D0.53=4.0)的同时,Ω2亦达到最大值。此时玻璃中Er3+所处环境的对称性降低而共价性增强。 相似文献
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A. E. H. Oehler M. C. Stumpf S. Pekarek T. Südmeyer K. J. Weingarten U. Keller 《Applied physics. B, Lasers and optics》2010,99(1-2):53-62
Stable ultrafast laser sources at multi-GHz repetition rates are important for various application areas, such as optical sampling, frequency comb metrology, or advanced high-speed return-to-zero telecom systems. We review SESAM-mode-locked Er,Yb:glass lasers operating in the 1.5 μm spectral region at multi-GHz repetition rates, discussing the key improvements that have enabled increasing the repetition rate up to 100 GHz. We also present further improved results with shorter pulse durations from a 100 GHz Er,Yb:glass laser. With an improved SESAM design we achieved 1.1 ps pulses with up to 30 mW average output power. Moreover, we discuss for the first time the importance of beam quality deteriorations arising from frequency-degenerate higher order spatial modes in such lasers. 相似文献
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We demonstrated a high-energy single-frequency erbium-doped yttrium aluminum garnet(Er:YAG)laser.With1470 nm laser diodes(LDs)as pumping sources,single-frequency laser pulses with energy of 28.6 m J,21.6 m J,and 15.0 m J are obtained at pulse repetition frequency of 200 Hz,300 Hz,and 500 Hz,respectively.As far as we know,this is the highest single-frequency pulse energy with the Er:YAG gain medium.With the ring cavity design,pulse duration is maintained at hundreds of nanoseconds.This high-energy single-frequency laser with hundreds of nanoseconds pulse duration is a prospective laser source for light detection and ranging applications. 相似文献
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Quinlan F Fortier TM Kirchner MS Taylor JA Thorpe MJ Lemke N Ludlow AD Jiang Y Diddams SA 《Optics letters》2011,36(16):3260-3262
We present an optical frequency divider based on a 200 MHz repetition rate Er:fiber mode-locked laser that, when locked to a stable optical frequency reference, generates microwave signals with absolute phase noise that is equal to or better than cryogenic microwave oscillators. At 1 Hz offset from a 10 GHz carrier, the phase noise is below -100 dBc/Hz, limited by the optical reference. For offset frequencies >10 kHz, the phase noise is shot noise limited at -145 dBc/Hz. An analysis of the contribution of the residual noise from the Er:fiber optical frequency divider is also presented. 相似文献
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Er3+-Yb3+共掺磷酸盐玻璃(LGS-L)波导放大器设计 总被引:16,自引:3,他引:13
就作者自行研制的Er3 + Yb3 + 共掺磷酸盐玻璃 (LGS L) ,用重叠积分方法进行放大器设计。在Er3 + 、Yb3 + 掺杂浓度分别为 1.5 1× 10 2 6ions/m3 、19.1× 10 2 6ions/m3 的情况下可获得 2 .6dB/cm的增益 ;Er3 + 掺杂浓度为2× 10 2 6ions/m3 时 ,在 4cm的器件上可获得超过 15dB的增益。此外 ,讨论了信号光和抽运光光场强度的横向分布与Er3 + 、Yb3 + 横向掺杂浓度分布之间的重叠对放大器增益的影响 ,放大器的最佳长度 ,以及在 980nm抽运下 ,Yb3 + 、Er3 + 掺杂浓度比对放大器增益的影响。 相似文献
7.
K. L. Vodopyanov 《Optics Communications》1998,150(1-6):210-212
Infrared pulses, continuously tunable in the 8–13 μm range, and with up to 1 MW peak power, have been achieved using single-stage frequency conversion in a CdSe travelling-wave optical parametric generator, pumped by 100 ps pulses from an actively mode-locked, Q-switched and cavity dumped 2.8 μm Cr,Er:YSGG laser. The external quantum conversion efficiency reached 10%. 相似文献
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Nd3+ strengthens the Er3+:2.7-μm emission 104 times in fluorophosphate glass;in addition,it can also decrease its upconversion effects and the 1.5-μm emission accordingly.Cross-relaxation process is the principal transition mechanism in this codoping system.Compared with Er3+ singly doped glass,JO parameters along with the Arad,β,τR values of Er3+ change markedly in Er3+:Nd3+ codoped glass because Nd3+ greatly in?uences the local environment around Er3+.Results also show that Nd3+ has a good 4I13/2 lifetime quenching effect as well as thermal load reduction ability for Er3+:2.7-μm emission. 相似文献
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Parameters of eyesafe lidar at 1.54 μm for detection of small plumes of smoke from burning wood or oil have been evaluated.
It was assumed that a diode-pumped solid-state Er:glass laser at 1.54 μm or a Nd:YAG laser with a Raman cell or optical-parametric
oscillator is used as a light source and that detection of backscattered light is performed with an avalanche photodiode.
Ash and soot particle size distributions were taken from experiments. A backscattering coefficient at 1.54 μm for various
source of smoke was estimated. In computing the laser energy, range between lidar and smoke, receiver optics diameter, fuel
mass burned in unit time, fire source radius, laser pulse duration and visibility were varied. Results of the computations
enabled estimation of the required laser energy, which ranges from 0.05 to 1400 mJ depending on the parameters.
Received: 5 January 2000 / Revised version: 3 March 2000 / Published online: 11 May 2000 相似文献
13.
We demonstrate an all-optical, thermally assisted technique for broad-range tuning of whispering gallery modes in microsphere
resonators fabricated from an Er:Yb co-doped phosphate glass (IOG-2). The microspheres are pumped at 978 nm and the heat generated
by absorption of the pump expands the cavity, thereby altering the cavity size and refractive index. We demonstrate a significant
nonlinear tuning range of greater than 700 GHz of both C- and L-band cavity emissions via pumping through a tapered optical
fibre. Finally, we show that large linear tuning up to ∼488 GHz is achievable if the microsphere is alternatively heated by
coupling laser light into its support stem. 相似文献
14.
B. G. Bravy V. M. Gordienko V. I. Kozlovsky Yu. V. Korostelin F. V. Potemkin Yu. P. Podmar’kov A. A. Podshivalov V. T. Platonenko V. V. Firsov M. P. Frolov 《Bulletin of the Russian Academy of Sciences: Physics》2016,80(4):444-449
Concept of a solid-state femtosecond laser system with a multigigawatt power level in the 4–5 μm range has been proposed. The system contains an ultrashort pulse seeder, a two-stage chirped pulse amplifier based on a broadband Fe2+:ZnSe active element with optical pumping by a YSGG:Cr:Er laser, and an output stage that provides additional nonlinear optical compression of an amplified pulse to approximately 30 fs in a dielectric CaF2 medium with anomalous group velocity dispersion in this spectral range. 相似文献
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用于光电仪器和相关测量的自混合干涉技术(特邀) 总被引:1,自引:0,他引:1
回顾了一种全新结构的干涉仪—自混合干涉仪(SMI)的发展情况。SMI由于其在激光器外部无需任何光学元件且应用范围广泛而倍受关注。SMI可用于测量与光路长度有关的一些量(如位移、小幅度振动、速度),也可用于测量弱光的回波(即回波损耗和隔离因子的测量)并可表征与介质相互作用特性相关的物理参数(如激光线宽、相干长度以及α因子等)。SMI是一种相干探测方法,其工作在靠近接收场的量子极限处,目前对散射目标物的最小探测幅值可达槡20 pm/(Hz)~(1/2)甚至更高,使用角锥棱镜使其计数步长为半波长,在动态范围为2 m时其分辨率约为0.5μm。另外,SMI结构紧凑、易于现场安装且可用于MEMS测试、旋转机械振动测试和生物运行测试等各种实验。 相似文献
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在过去的几十年人们对Er3+掺杂的玻璃材料进行了广泛的研究,因为Er3+的4Ⅰ13/2→4Ⅰ15/2跃迁能够给出适合红外光通讯窗口的1.5 μm的发射.据我们所知,目前关于脉冲激光激发下Er3+掺杂材料1.5 μm发射的动力学行为研究报道仍很少.我们引入了转移函数理论,研究了980nm脉冲激发下Er3+的4Ⅰ13/2能级荧光的动力学行为.发现在980nm脉冲激发后,其荧光衰减遵循双指数规律,4Ⅰ13/2能级布居分为指数上升和指数下降两个过程. 相似文献
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Jessica Barrientos Barria Alexandre Dobroc Hélène Coudert-Alteirac Myriam Raybaut Nicolas Cézard Jean-Baptiste Dherbecourt Thomas Schmid Basile Faure Grégoire Souhaité Jacques Pelon Jean-Michel Melkonian Antoine Godard Michel Lefebvre 《Applied physics. B, Lasers and optics》2014,117(1):509-518
We report on the remote sensing capability of an integrated path differential absorption lidar (IPDIAL) instrument, for multi-species gas detection and monitoring in the 3.3–3.7 µm range. This instrument is based on an optical parametric source composed of a master oscillator-power amplifier scheme—whose core building block is a nested cavity optical parametric oscillator—emitting up to 10 µJ at 3.3 µm. Optical pumping is realized with an innovative single-frequency, 2-kHz repetition rate, nanosecond microchip laser, amplified up to 200 µJ per pulse in a single-crystal fiber amplifier. Simultaneous monitoring of mean atmospheric water vapor and methane concentrations was performed over several days by use of a topographic target, and water vapor concentration measurements show good agreement compared with an in situ hygrometer measurement. Performances of the IPDIAL instrument are assessed in terms of concentration measurement uncertainties and maximum remote achievable range. 相似文献
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分析了Er3+离子的能级结构特性和Er:YAG四能级系统的激光速率方程。采用了双灯,双椭圆腔和窄脉冲放电等方式提高了抽运效率; 通过提高激光谐振腔的反射率,降低阈值,从而实现了输出2.94 μm的高重频窄脉冲激光; 采用高压高速层流冷却技术降低了热效应的影响。Er3+:YAG激光器的重复频率为40 Hz,单脉冲输出能量为0.5 J,满足实际应用需要。 相似文献
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We have demonstrated more than 3 W of average output power from a 2.94-mu;m quasi-cw diode-pumped total internal reflection (TIR) Er:YAG laser operating at 100 Hz with a 4% duty cycle. Moreover, repetition rates of up to 600 Hz at more than 1.2-W output power have been achieved. The cavity consists of a plane-mirror resonator of 40-mm length and uses three of five TIR regions within the laser crystal as pump facets to efficiently couple the pump energy into the resonant laser mode. Differential efficiencies of up to 18.3% have been achieved at an optimum pump pulse width in the range of 300 micros . 相似文献
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We measured the optical decoherence times T2, or, equivalently, the homogeneous line width, in an Er-doped optical fiber at low temperature as a function of external magnetic field and temperature using two-pulse photon echoes. The decoherence times were up to 230 ns at fields above 3 T. The magnitude of the line narrowing induced by a magnetic field of 3 T is 2.5 MHz, which is anomalously large compared to that typical for oxide crystals with similar Er3+ concentration. This is interpreted as evidence for dephasing by coupled spin-elastic tunneling modes where the normal glass tunneling modes acquire a magnetic character by coupling to the Er3+ spin. 相似文献