一种新型有机倍频材料——苯基脲的倍频性能研究

报道了一种新型优质有机倍频材料———苯基脲并对其进行了初步研究.苯基脲具有很强的二阶非线性光学效应,其粉末二次谐波产生效率为尿素的11倍 截止吸收波长为λcutoff=290nm,有很宽的透光波段 抗光损伤实验表明,苯基脲具有较高的抗光损伤阈值 并且晶体生长习性良好.计算分析了苯基脲的微观二阶非线性光学性质. 关键词：     

一种新的亚酞菁的共振三阶非线性光学性质

用简并四波混频技术研究了一种新的亚酞菁(三新戊氧基溴硼亚酞菁)的三阶非线性光学性质.测得纯固体三新戊氧基溴硼亚酞菁的三阶非线性极化率χ(3)pure和分子二阶超极化率〈γ〉分别为69×10-10esu和30×10-31esu.χ(3)pure的响应时间为20ps.并对这些结果进行了讨论 关键词：     

POPULATION TRAPPING IN MULTI-LEVEL SYSTEM VIA QUANTUM INTERFERENCE

Population trapping via quantum interference in a multi-level system driven by a coherent field is investigated. The influences of the alignment of the transition dipole moments and the energy-level separation of the upper levels are taken into account. Detailed trapping population profiles under the different conditions are given. The research result is helpful for simplifying the theoretical model and selection rational energy level system.     

Spectroscopic and lasing characteristics of 1,3,5,7-tetramethyl-8-ethyl-pyrromethene-BF_2 complex

The basic optical properties of the newly synthesized pyrromethene-BF2 derivative (Compound 1) were investigated systematically by its ultraviolet to visible (UV-visible) absorption, fluorescence and triplet-triplet absorption. Its lasing characteristics were measured on a dye laser system pumped by a continuous wave Ar ion laser. The results suggest that, compared with the typical pyrromethene-BF2 dye such as P-546, Compound 1 possesses stronger fluorescence and lower triplet-triplet absorption over its fluorescence spectral region. Excellent laser properties were also observed for Compound 1. It outperforms the commercially available benchmark laser dye rhodamine 6G in laser wavelength tuning range, which proves that Compound 1 is probably a potential candidate to be developed as the all-solid-state laser material.     

Study on optical nonlinearities of ZnO-Nb2O5-TeO2 glass with time-resolved four-wave mixing technique

We investigated nonlinear optical properties of ZnO-Nb2O5-TeO2 glass excited by a femtosecond laser with time-resolved four-wave mixing (FWM) technique. The unusual FWM signals were observed in samples with ZnO dopant. The mechanism for the optical nonlinearities was discussed.     

Nonlinear Optics properties of Er2O3- doped 75Nb2O5-20TeO2-5ZnO glasses

We have performed time-resolved degenerate four-wave mixing(DFWM)experiments in 75Nb2O5-20TeO2-5ZnO glasses doped by Er2O3 at different excitation intensities and lattice temperatures.DFWM signalexhibits three peaks at high excitation intensities,where a main peak appears at zero time delay and tworather weak side peaks locate symmetrically at the negative and positive time delay,respectively.Themain peak is attributed to local-field effect and two side peaks are attributed to Coulomb interaction(CI).     

4f结构脉冲整形器失调对光场空间分布的影响

利用零色散脉冲整形装置的模型，从理论上详细讨论了4f结构脉冲整形装置中第一光栅和第一凸透镜之间距离失调、两凸透镜之间距离失调以及第二凸透镜与第二光栅之间距离失调对输出脉冲空间特性的影响。     

Study on optical nonlinearities of ZnO-Nb_2O_5-TeO_2 glass with time-resolved four-wave mixing technique

We investigated nonlinear optical properties of ZnO-Nb2O5-TeO2 glass excited by a femtosecond laser with time-resolved four-wave mixing (FWM) technique. The unusual FWM signals were observed in samples with ZnO dopant. The mechanism for the optical nonlinearities was discussed.     

CdTe/CdS核壳结构量子点超快载流子动力学

在水相合成CdTe以及CdTe/CdS核壳结构量子点基础上, 利用基于抽运-探测技术的瞬态差分透射技术研究了CdTe量子点以及不同CdS壳层厚度的CdTe/CdS量子点的最低激子能态的超快激发与弛豫动力学. 研究表明:相比于CdTe,CdTe/CdS量子点的电子空穴由于空间分离,其所需的激发时间要长于电子空穴空间重叠态所需要的激发时间.随着壳层厚度的增加, 量子点表面的钝化有效地减少了表面态相关弛豫机理,并延长相对应的弛豫时间.     

猴子大脑皮层组织的拉曼光谱研究

猴子的大脑皮层主要由灰质和神经元组成,是大脑中调控行动和思维的区域。选取在生命成长过程中具有代表性的3个年龄段(幼年、成年、老年)猴子的大脑皮层组织,首次测得其拉曼光谱。实验结果显示,3个不同年龄段的猴子大脑皮层的拉曼光谱最明显的差异表现在1 000～1 400 cm~(-1)和2 800～3 000cm~(-1)范围内。随着年龄的增长,归属于脂类的拉曼峰1 313和2 885 cm~(-1)的强度越来越强,而归属于蛋白的拉曼峰1 338和2 932 cm~(-1)的强度却逐渐减弱,并且在老年猴子大脑皮层的拉曼谱中出现了2个归属于脂类的拉曼峰1 296和2 850 cm,I_(1313)/I_(1338)和I_(2885)/I_(2932)的变化趋势很好地描述了这种差异。研究表明,随着年龄的不断增长,猴子大脑皮层中脂类的含量逐渐增加,这样可以很好地说明大脑皮层中脂类的聚积是导致衰老的一个重要原因,为进一步研究人类和动物的生命活动规律、疾病的形成机理提供了很有价值的参考。