Directional excitation of Bloch surface waves by laser-printed Mie nanoparticles

Abstract

Direct printing of semiconductor nanoparticles via laser-induced transfer is a recently developed tool to obtain individual nanoparticles or their arbitrary arrays on a substrate of almost any shape and material. Semiconductor nanoparticles supporting Mie resonance are now widely explored in the pursuit for the novel all-dielectric photonic platforms. The promising direction is merging Mie-resonant nanoparticles with photonic crystals. We experimentally demonstrate excitation of a Bloch surface wave in photonic crystal mediated by an individual silicon nanoparticle. The nanoparticle being irradiated by light with the wavelength near the Mie resonance acts as a nanoantenna and allows excitation of the Bloch surface wave from the far-field. Visualization of the surface wave propagation direction is performed by the Fourier-plane imaging using the leakage radiation microscopy setup. We show that tuning the wavelength of the incident light around the Mie resonance allows for launching Bloch surface wave in both forward and backward direction.