铌酸锂质子交换波导中切伦科夫倍频实验研究

报道了质子交换铌酸锂平板波导中切伦科夫倍频蓝绿光输出研究。理论上计算了质子交换波导参数对不同基波波长倍频转换效率的影响。制备出适合于蓝绿光输出的铌酸锂质子交换波导并观测到较高转换效率的倍频光产生,实验中我们测量了倍频转换效率与抽运动率以及抽运波长的关系,实验结果与理论预测吻合。     

Ar+激光激发的LiArA2Ⅱ→X2∑漫射谱发射

用Ar⁺的457.9,476.5,496.5,514.5nm激光激发充有Ar气的Li热管,获得Van der Waal's分子LiAr在650—760nm波长范围A²П→X²∑的漫射发射光谱。讨论了产生这种发射的动力学机制。 关键词：     

Theoretical study of quasi-phase-matching fourth harmonic generation in periodically poled lithium tantalate

The direct fourth harmonic generation (FHG) is theoretically demonstrated based on quasi-phase-matching (QPM) configuration in periodically poled lithium tantalate (PPLT). The wavelength dependence of the period of FHG QPM gratings is calculated. Bandwidths of fundamental wavelength, temperature, and incident angle are also studied. A very wide bandwidth, as large as 119.5 nm, of fundamental wavelength near 3699 nm is found with the QPM period of 9.442 μm and the crystal length of 1 cm.     

由前向四波混频产生脉冲压缩态光场

本文提出一个方案,用锁模激光脉冲序列相干泵浦一个具有三阶极化率的非线性介质,经由前向四波混频产生脉冲压缩态光场,采用激光脉冲序列作为本地振荡对压缩态光场进行平衡零差检测。理论结果表明,本方案不但可以获得光强很强的压缩态光场输出,而且可以获得几乎完全压缩的脉冲序列形式的压缩噪声功率谱,其脉冲序列谱形状和输入光脉冲序列谱形状相反。 关键词：     

Generation of multi-wavelength light sources for optical communications in aperiodic optical superlattice

A method for generating multi-wavelength light source is theoretically investigated by optical parametric oscillation (OPO) in aperiodic optical superlattice (AOS). The effects of domain errors caused by the room-temperature electric poling process are checked. The relationship between the linewidth and the block length is also discussed.     

Optimized Second Harmonic Generation of Femtosecond Pulse by Phase-Blanking Effect in Aperiodically Optical Superlattice

In order to minimize the effect of the unconsidered frequency components on the generated compression pulse, the phasing-blanking effect is taken into account of designing the one~dimensionai aperiodic domain reversal structure. Hierarchic genetic algorithm for the design of a domain reversal grating to modulate the spectrum and phase of the generated SH pulse simultaneously are presented. Our simulation shows that the quality of an output pulse is fairly improved.     

Large Relative Raman Shift for Molecules Adsorbed on Metallic Nano-particles

The enhancement of two order-of-magnitudes is observed in surface-enhanced Raman spectroscopy （SERS） of gases （CO, C2H2, C2H4, etc） adsorbed on nitric acid-roughened metal foil. In addition, some Raman lines of gases adsorbed on these active substrates show larger frequency shifts and linewidth broadening, compared with the Raman spectroscopy of free gases. Using the two-oscillator electromagnetic model, we explain this phenomenon. It is related to the large non-regular particles on the active substrate we prepared. It is found that the parameters of the surface-plasmon dispersion, the distance of molecules from the surface and the radius of particles play crucial roles on the relative large Raman shifts.     

ArCN三原子准分子的研究(Ⅰ)——电子态的量子化学计算

分别采用６－３１Ｇ＊，６－３１Ｇ?＊基组对线性ＡｒＣＮ分子的X²∑⁺，Ａ²∏_i，Ｂ²∑⁺，Ｃ²∏_i，Ｄ²∑⁺和Ｅ²∏_r ６个电子态进行了从头计算法开壳自旋限制Ｈａｒｔｒｅｅ－Ｆｏｃｋ（ＲＯＨＦ）计算。计算结果表明线性ＡｒＣＮ分子的电子态具有典型的准分子结构，从而可以肯定ＣＮ与稀有气体原子Ｒｇ（Ａｒ，Ｋｒ，Ｘｅ）能够形成自由基准分子。对Ｘ²∑⁺，Ａ²∏_i的自旋非限制Ｈａｒｔｒｅｅ－Ｆｏｃｋ（ＵＨＦ）计算证实较大的自旋污染不影响势能曲线的形状。 关键词：     

15波长输出的布里渊掺铒光纤激光器

多波长布里渊掺铒光纤激光器是一种新型的多波长光纤激光器,其原理是利用受激布里渊增益和掺铒光纤的线性增益,可以在常温下得到波长间隔约为0．08nm(～10GHz)的多波长输出。报道的布里渊掺铒光纤激光器,在布里渊抽运功率为1．7mW、980nm抽运功率为300mW的情况下得到稳定的15个波长(间隔～10GHz)的输出,这种激光器用作光传感器、光谱分析仪以及密集波分复用系统的光源。实验发现,输出波长的个数随着980nm抽运功率的增大而增加。另外,布里渊掺铒光纤激光器的信号功率主要来自于掺铒光纤的增益,而布里渊增益对它的影响不大。     

晶体球法直接测量KTP晶体第Ⅰ类相位匹配曲线

报道了35ps激光脉冲射入直径为10mm KTP昌体球的第Ⅰ类相位匹配二次谐波产生实验,根据二次谐波产生转换效率直接测量了KTP晶体的第Ⅰ类相位匹配曲线及相应的有效非线性系数,并与6组色散方程给出的理论匹配曲线比较,指出Vanherzele的公式优于其他五组。