Geometrical condition for observing Talbot effect in plasmonics infinite metallic groove arrays

• 来源期刊: 中国物理B（英文版）
• 关键词: Talbot image surface plasmon polaritons groove array
• 年，卷（期）: 2018,（12）
• 页码范围: 332-338
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/12/124204

摘要

The plasmonics Talbot effect in metallic layer with infinite periodic grooves is presented in this study. Numerical ap-proach based on the finite element method is employed to verify the derived Talbot carpet on the non-illumination side. The groove depth is less than the metallic layer thickness;however, for specific conditions, surface plasmons polaritons (SPPs) can penetrate through grooves, propagate under the metallic layer, and form Talbot revivals. The geometrical parameters are specified via groove width, gap size, period, and wavelength, and their proper values are determined by introducing two opening ratio parameters. To quantitatively compare different Talbot carpets, we introduce new parameters such as R-square that characterizes the periodicity of Talbot images. The higher the R-square of a carpet, the more coincident with non-paraxial approximation the Talbot distance becomes. We believe that our results can help to understand the nature of SPPs and also contribute to exploring this phenomenon in Talbot-image-based applications, including imaging, optical systems, and measurements.