Study of Low-Loss Ge25Sb10S65 Chalcogenide Waveguides by Stimulated Brillouin Scattering (CAT#: STEM-ST-0125-YJL)

Introduction

Since the GeSbS has a high refractive index and an acoustic velocity (~2.6 km/s) lower than that of the silica cladding (~3.7 km/s), it allows confinement of both optical and elastic waves within the waveguide core by total internal reflection, enabling efficient Brillouin interactions. The GeSbS has several distinct advantages as compared to the As2S3. First, owing to its high glass transition temperature (>300 ℃), the GeSbS waveguide core is robust during the fabrication process that uses the traditional CVD method for silica cladding, resulting in low propagation loss. In addition, the GeSbS material is free from the arsenic component and thus environmental-friendly. Moreover, the GeSbS waveguide has a high damage threshold due to its high transition temperature, which is desirable to obtain a high Brillouin gain. Therefore, the GeSbS chalcogenide platform has a great potential for the implementations of a broad range of on-chip SBS functionalities.