A novel all-optic tunable long-period grating using a unique double-cladding layer

Abstract

In this paper, a novel all-optic tunable filter based on long-period grating (LPG) with a unique double-cladding layer structure is implemented. The LPG that has an ultra-thin silica inner cladding layer and a dye-doped liquid crystal outer cladding layer is tuned by photochemical driving liquid-crystal molecular reorientation. The unique feature of this tunable filter is that there is no contact electrodes required, which may make the fabrication of tunable filter easier.