Optical investigation of chalcogenide glass for on-chip integrated devices

Chalcogenide glass (ChG) has been fabricated into on-chip integrated waveguides owing to its high nonlinear refractive index. However, the systematic research of Ge-Sb-S glass shows that Ge25Sb10S65 glass has greater hardness and stronger resistance to laser damage than other component glasses considered in this study. Additionally, the high nonlinear refractive index of Ge25Sb10S65 glass makes it a suitable base material for on-chip integrated devices. To further verify the application potential of this glass in integrated photonics, a waveguide based on Ge25Sb10S65 glass, with width W = 2 μm and thickness H = 1.4 μm, was engineered for supercontinuum generation (SCG). A monolithically integrated SCG spanning from 870 nm to 2480 nm is obtained, when pumped by a femtosecond laser at a central wavelength of 1.55 μm, with a repetition rate of 1 MHz. The results indicated that the Ge25Sb10S65 glass has great prospects of utilization in on-chip integrated devices for application in optical frequency combs (OFCs) or SCG.