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951.
采用光谱物理公司生产的,平均输出工为1.1W,脉宽为90fs的再生锁模掺钛蓝宝石(Ti:Sapphire)激光器作为泵浦源,KTP作为非线性光学介质,以及BBO作为腔内倍频晶体,制成了一台同上泵浦腔内倍频飞秒KTP光学参量振荡器,其输出调谐范围528nm至586nm,最佳平均输出功率为240mW左右,脉宽约为100fs。在无反馈伺服系统的情况下,该参量振荡器可维持振荡达三个小时。 相似文献
952.
Dmitri Toptygin 《Journal of fluorescence》2003,13(3):201-219
It is well known that the probabilities of radiative transitions in a medium differ from those in vacuum. Excitation of a fluorescent molecule and its radiative decay are examples of radiative transitions. The rates of these processes in solution depend on the optical characteristics of the solvent. In this article the radiative decay rate and the extinction coefficient of a fluorescent molecule in solution are expressed in terms of the intrinsic properties of the fluorescent molecule (electronic transition moments) and the optical characteristics of the solvent (refractive index, group velocity of light). It is shown that the group velocity does not enter in the final expressions for the radiative decay rate and the extinction coefficient; this means that the dispersion of the refractive index has no effect on these quantities. The expressions for both the radiative decay rate and the extinction coefficient contain the refractive index of the solvent and the local field correction factor. The latter depends on the cavity model, and, for some cavity models, on the shape of the cavity. Four types of cavity models are discussed; for each model the limits of applicability are examined. Experimental evidence in support of specific cavity models is reviewed. 相似文献
953.
Shinobu Ohara Shigeru Yamaguchi Masamori Endo Kenzo Nanri Tomoo Fujioka 《Optical Review》2003,10(5):342-345
Performance characteristics of power build-up cavity (PBC) as the light source of a Raman spectroscopy based gas sensor were studied. The key parameter to optimize stable and high intra-cavity power operation was beam diameter of the back reflected beam from external cavity to diode laser. The optimum diameter determined by an appropriate distance between the cavity and diode laser was found to be comparable with the waveguide cross section of diode laser for the effective spatial filtering, where inevitable cavity coupling loss caused by slight spatial mode mismatching existed. A PBC with a finesse of ∼10300 achieved a stable TEM00 mode in excess of intra-cavity power of 80 watts pumped by a 10 milliwatts diode laser. Simultaneously, the PBC wavelength is found to be passively locked effectively at 670 +/− 0.15 nm where the center of the gain region exists. A Raman spectrum of nitrogen measurement was demonstrated. 相似文献
954.
A novel Yb3+-doped fiber ring cavity laser pumped by a 977 nm laser diode is presented with its output laser wavelength of 1060 nm. Based on a fiber Bragg grating (FBG), the laser exhibits 0.20 nm line-width, 7.5 mW laser output power, 40 dB signal-to-noise ratio (SNR) and 66% slope efficiency. 相似文献
955.
1 Introduction Laserdiodepumpedsolid statelasershaveadvantagesofhighefficiencyand goodbeamquality .However ,thethermallyinducedlensingainmaterialslimitstheoutputpoweroflaserswithgoodbeam qualitytoanarrowpowerrangeandmakesthebeamdiameter ,beamdivergencean… 相似文献
956.
957.
本文对球体谐振腔与法布里-珀罗腔作了比较。详细讨论了球体腔中产生的喇曼振荡、振荡输出谱及场分布等特性。从水滴及酒精液滴的实验结果分析了输出共振和输入共振,对实验中还观察到的液滴中的高阶斯托克斯振荡和组合斯托克斯振荡作了讨论。 相似文献
958.
The cavity field spectrum of a two-level atom interacting with two modes of the radiation field through intensity-dependent coupling in an ideal cavity is investigated. The results for the initial fields in pure number states, coherent states, and squeezed vacuum states are calculated. We find that the frequency of one mode is tuned by the intensity of the other mode when the two modes are both in pure number states or coherent states. A complicated multipeak structure appears when both field modes are in a superposition of number states initially. 相似文献
959.
960.