Tungsten disulfide coated side‐polished fibre as polarisation state modulator in all‐optical system

Abstract

Abstract In this work, all‐optical polarisation state modulation using a tungsten disulfide (WS2) coated side‐polished fibre (SPF) as modulator is experimentally demonstrated. A bulk layer WS2 is exfoliated into a few‐layer WS2 thin film using liquid phase exfoliation technique. The few‐layer WS2 film is then coated onto a SPF to serve as an optical polarisation state modulator based on the thermo‐optic effect. The rotation of the polarised signal light is controlled using a pump laser. Throughout the pump power range of 514.5 mW, the polarisation state of the polarised signal light has rotated ∼70°, with a minor ellipticity fluctuation of <6°. The proposed experiment is carried out on the basis of the photon‐modulate‐photon principle and achieved all‐optical modulation in a fibre laser system.

Keywords

• light polarisation
• modulation