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551.
In this paper, the stability of a laser-diode-pumped Cr4+∶YAG passively Nd3+∶YAG Q-switched laser and the influence of the transversal mode structure on the stability are investigated. With the laser operating in TEM00 mode, the pulse energy fluctuation and the repetition rate fluctuation as functions of the repetition rate are measured, and semi-quantitatively and qualitatively analyzed, respectively. 相似文献
552.
QIU Yishen LU Tuansun HUANG Wenchai ZHENG Zhiqiang ZHUANG Jian TANG Dingyuan 《Chinese Journal of Lasers》2000,9(5):452-458
A new method generating multiple-beams mutually pumped phase conjugation (MMPPC) in a photorefractive Bat- xSrxTiO3 crystal is demonstrated, in which a pumping beam is incident upon a-face of the crystal and two signal beams are introduced into + c face of the crystal with the almost same incident angle and position. The time evolution of the phase conjugations from signal beams and the dependence of phase-conjugate reflectivities on the input-beam intensity ratios are presented. Also, the amplitude coupled-wave equations based on the model of two interaction reigns is derived. The results obtained by numerical calculation of the corresponding coupled-wave equations show qualitative agreement with the experimental results. 相似文献
553.
554.
Three luminescence bands in the yellow and red spectral region, which are related to the 1Δg1Δg→3Σg− 3Σg− double electronic transition of O2, have been investigated in the , β, and γ phase of solid oxygen. The temperature dependence of the intensity of the yellow band is strongly influenced by emission from higher vibrational levels of O2(1Δg), which are populated by anharmonic V–V pumping. The broken mirror symmetry of the luminescence and absorption bands in the phase of solid O2 points to an interaction between the electrons and the elementary excitations of the crystal, which is different in the ground and excited electronic states, e.g., a quadratic electron–phonon interaction. 相似文献
555.
研究了二极管端面泵浦的附加脉冲锁模的Nd:YAG激光器并分析了脉冲压缩原理及自启动机制,在最大泵浦功率为2.4W时,得到重复频率为134MHz、脉宽为2ps、有效输出功率76mW、相应峰值继283W、波长为1.053μm、波长为1.053μm的稳定的连续模脉冲序列。 相似文献
556.
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558.
The results of a comparative study (theoretical and experimental) of two original approaches for spectral control of two-wavelength pulsed Ti:sapphire (Ti:S) lasers and the most popular conventional methods are presented. Single line operation as a particular case is considered. We compare our own methods: (i) combined dual pulse pumping–passive self-injection locking (DPP–PSIL) and (ii) coupled cavity dye laser injection locking (CCLIL) with the conventional methods: (i) intracavity selection (IS), (ii) PSIL and (iii) traditional injection locking using an external dye laser. The most important criteria—laser efficiency, emission line width, tuning range, spectral purity and buildup time are compared under optimized conditions. The comparison is made using the same pump source with constant output energy in each case. The results serve as a basis for choosing correctly the most suitable spectral control technique for a particular Ti:S laser application. It is shown that the DPP–PSIL method guarantees a remarkable improvement of the Ti:S laser performance (nearly doubling the laser efficiency with the same line width and comparable laser tuning range as IS, combined with a protection of the selectors). The CCLIL approach assures a maximum laser efficiency in narrow line emission in addition to a minimal and reproducible buildup time. The IS method provides a maximal tuning range. 相似文献
559.
An analytic model for first Stokes–Raman generation in optical fiber is used to evaluate the relative importance of quantum initiation noise and amplified classical pump noise in recent experiments on noise shaping. The model accounts for pump depletion and for fluctuations arising from the spontaneous generation of the first Stokes pulse, but not for scattering into higher-order Stokes pulses. The model reproduces the qualitative features of the measured first Stokes pulse energy statistics using realistic parameter values. 相似文献
560.
报道准连续60W半导体激光二极管侧面泵浦的锁模调QNd:YAG板条激光器,调Q锁模的激光脉冲宽度(FWHM)为60ps,调Q脉冲包络宽度为250ns,积分能量163μJ,最大锁模脉冲的峰值功率超过100kW。 相似文献