Engineering the Phase Front of Light with Phase-Change Material Based Planar lenses

• DOI: 10.1038/srep08660
• Publication Date: 2015-03-02T10:15:28Z
• Authors: Yiguo Chen; Xiong Li; Yannick Sonnefraud; Antonio I. Fernán...; Xiangang Luo; Minghui Hong; Stefan A. Maier
• Keywords: Nanophotonics

Abstract A novel hybrid planar lens is proposed to engineer the far-field focusing patterns. It consists of an array slits which are filled with phase-change material Ge 2 Sb Te 5 (GST). By varying crystallization level GST from 0% 90%, Fabry-Pérot resonance supported inside each slit can be spectrally shifted across working wavelength at 1.55 µm, results in a transmitted electromagnetic phase modulation as large 0.56π. Based on this geometrically fixed platform, different fronts constructed spatially plane by assigning designed levels corresponding slits, achieving various The present work offers promising route realize tunable nanophotonic components, used optical circuits and imaging applications.