Functional photonic nanostructures based on Mie-resonant semiconductor nanoparticles (Conference Presentation)

Abstract

Nanoparticles composed of high refractive index semiconductors can support strong localized Mie-type resonances of electric and magnetic multipolar character that can be tuned by the nanoresonator geometry [1]. In addition, such semiconductor nanoresonators can exhibit very low absorption losses at optical frequencies. Based on these unique optical properties, semiconductor nanoresonators represent versatile building blocks of functional photonic nanostructures with tailored optical properties. This talk will provide an overview of our recent advances in controlling the generation and propagation of light with dielectric nanostructures composed of silicon or other high-index semiconductor nanoresonators. First, I will focus on passive and linear silicon metasurfaces designed to impose a spatially variant phase shift onto an incident light field, thereby providing control over its wave front. Based on the simultaneous excitation of electric and magnetic dipole resonances, silicon nanoresonators can be tailored to emulate the behaviour of the forward-propagating elementary wavelets known from Huygens’ principle [2]. This concept allows for the realization of various wave front shaping devices with high transmittance efficiency, full phase coverage, and a polarization insensititve response [3,4]. I will then discuss how we can utilize semiconductor nanoresonators for tailoring spontaneous emission from nanoscale light sources as well as for the manipulation of nonlinear effects in semiconductor nanoparticles. [1] I. Staude et al., ACS Nano 7, 7824 (2013). [2] M. Decker et al., Adv. Opt. Mater. 3, 813 (2015). [3] K. E. Chong et al., Nano Lett. 15, 5369–5374 (2015). [4] K. E. Chong et al., ACS Photonics 3, 514-519 (2016).