金膜的纳米孔结构在线偏振光下产生涡旋阵列

A VORTEX ARRAY GENERATED BY A NANOHOLES GOLD FILM ILLUMINATED WITH LINEARLY POLARIZED LIGHT

通过在金膜上刻蚀纳米孔结构,我们用线偏振光照射样品表面并在一定衍射距离处采集衍射场的信息而得到七个有序排列的涡旋组成涡旋阵列.实验中我们搭建了马赫-曾德尔干涉仪,用CCD记录在样品远离物面不同距离处产生的衍射场和在有参考光照射下产生的干涉条纹图.在得到的光强图样中出现了七个涡旋有序排列中心处,我们称之为七涡旋阵列.通过改变衍射距离,我们观察了七涡旋阵列的演化.此外,我们利用傅里叶变换的方法提取了光强图样对应的相位分布.

We obtain a vortex array with seven vortices at a certain diffraction distance in the diffraction fields generated by a gold six nanoholes film illuminated with linearly polarized light. In the experiment, we set up a Mach -Zehnder type interferometer. A CCD is used to record the diffraction fields and the interference pattern of the diffraction fields and reference beam at different distances from the object plane. In the intensity pattern, we note that seven well -ordered vortices appear in the central area, and we call them as a vortex array with seven vortices. By changing the diffraction distance, we observe the evolvement of the vortex array. In addition, we reconstruct the phase distribution corresponding to the intensity pattern with the Fourier transform method.