飞秒强激光对二氧化钛金红石晶体相变的影响

该文章报道了利用显微激光拉曼光谱仪研究近红外飞秒强激光脉冲诱导二氧化钛金红石单晶所引起的相变.实验辐照时间为60s,当激光辐照平均功率增加时,锐钛矿相的拉曼振动模式强度增强,金红石相的拉曼振动模式强度减弱.通过金红石相和锐钛矿相粉体等拉曼光谱的实验,肯定了随着辐照激光功率的增大,.可以通过拉曼光谱中锐钛矿A1g B1g(515 cm-1)振动模式标志峰和金红石相Eg(445 cm-1)振动标志峰分别对应面积的比判断其相变量.     

Femtosecond pulse laser-induced self-organized nanostructures on the surface of ZnO crystal

This paper reports self-organized nanostructures observed on the surface of ZnO crystal after irradiation by a focused beam of a femtosecond Ti：sapphire laser with a repetition rate of 250kHz. For a linearly polarized femtosecond laser, the periodic nanograting structure on the ablation crater surface was promoted. The period of self-organization structures is about 180 nm. The grating orientation is adjusted by the laser polarization direction. A long range Bragglike grating is formed by moving the sample at a speed of 10μm/s. For a circularly polarized laser beam, uniform spherical nanoparticles were formed as a result of Coulomb explosion during the interaction of near-infrared laser with ZnO crystal.     

借助Excel程序处理光电效应及普朗克常数的测定实验数据

以光电效应及普朗克常数的测定实验为例,介绍了excel软件在实验数据处理中的应用。与传统的手工处理实验数据相比,Excel软件简化了计算过程,提高了计算结果的准确性,增强了学生的整体素质,为学生将来的工作和科研学习奠定了基础。     

Mg-Co-Ti共掺杂对M型钡铁氧体磁性能的影响

采用溶胶-凝胶方法制备了不同Mg-Co-Ti掺杂量的Ba(MgCo)_x/2Ti_xFe_11.5-2xO₁₉磁性粉体，运用XRD和SEM对样品成分及颗粒大小进行了表征，并运用VSM测试了样品的磁性能。结果表明：所制备的粉体1100℃煅烧2小时，粉体结晶良好，呈纯相结构，粉体颗粒大小平均在250 nm左右。随着掺杂含量x从0.1增加到0.6，矫顽力Hc从342 kA/m下降至143 kA/m，而饱和磁化强度Ms先增加，随后降低，在x=0.3时获得最大Ms为55.27 Am²/kg。剩余磁化强度Mr，随着掺杂含量x的增加，先增加，然后逐渐减少。当x=0.3时剩余磁化强度最大值为30.90 Am²/kg。研究表明，可以通过在Fe位掺杂不同含量的Mg-Co-Ti，调整钡铁氧体的磁性能，以适应不同的应用需求。