用椭偏术研究与接触介质有关的贵金属的介电函数

为了研究接触介质对金属光学性质的影响，实验中使用具有不同折射率的梯形棱镜作为衬底，将金和银蒸发到棱镜底部，用椭偏术分别测量了薄膜在金属-空气、金属-衬底界面的介电函数.结果表明：无论在Drude区，还是在带间跃迁区，金属-衬底界面处薄膜介电函数不仅与金属-空气界面处的测量值不同，而且随衬底折射率改变而改变.在固体接触条件下获得的结果与其他作者在液体接触条件下获得的结果相一致，但尚难被现有机制所解释. 关键词：

ELLIPSOMETRIC STUDY OF THE MEDIUM-RELATED DIELECTRIC FUNCTIONS OF NOBLE METALS

To study the influence on the optical properties of metal imposed by neighboring medium,we used Dove prisms with different refractive indexes as the substrate in experiment.The noble metal films of Au and Ag were deposited on the bottom of prisms.The dielectric functions for films at the metal-air and metal-substrate interfaces were measured by the spectroscopic ellipsometric method.We found that the dielectric functions of the film measured at the metal-substrate interface do change with the refractive index of the neighboring medium and differ from that measured at the metal-air interface in both the Drude and interband transition regions.The results obtained in a solid-contacting configuration agree with those observed by other authors in a liquid-contact condition,however they cannot be well understood by the known mechanisms.