Optics letters | 2019
Efficient arsenic trisulfide vertical grating coupler on lithium niobate for integrated photonic applications.
Abstract
An efficient vertical grating coupler design for arsenic trisulfide (As2S3) on silicon dioxide (SiO2) on lithium niobate (LN) is proposed, fabricated, and experimentally verified. We report 4\xa0dB coupling efficiency per grating for vertical fiber coupling at a wavelength of 1550\xa0nm with a 3\xa0dB bandwidth of 40\xa0nm using an aluminum reflector mirror between the LN and SiO2 interface. This coupler is the first step towards the demonstration of high-performance integrated photonic devices, which would simultaneously benefit from the acousto-optic properties of As2S3 and electro-optic and acoustic properties of LN. This hybrid platform is deemed to impact a broad range of applications such as imaging, ranging, and inertial sensing.