Wavelength manipulation in a grating metasurface loaded Bloch surface wave structure

Abstract

We report the realization of a wavelength interrogated Bloch surface wave device structure by exploiting the surface properties via introducing a dielectric grating metasurface on top of a photonic crystal slab. A general dispersion relation based on impedance approach is adopted as the guideline to design the proposed structure. The sustained Bloch surface wave mode along the interface between the dielectric grating metasurface and the external medium can be manipulated by properly tuning the structural parameters. Comprehensive theoretical and numerical investigations regarding the effects of the grating metasurface on the surface mode’s properties, including the reflection properties, dispersion relation as well as the enhanced electronic field have been conducted. With these results, the existence of Bloch surface mode in the band-gap can be determined and it is revealed that the structure is capable of tuning the resonance wavelength by satisfying the excitation condition, thus making it a promising candidate for high-sensitive optical sensing.

Keywords

• Optics at surfaces
• Bloch surface wave
• Dielectric grating
• Photonic crystal
• Optical sensing