Ultra-compact acousto-optic modulation using on-chip integrated Bragg gratings on lithium niobate-chalcogenide hybrid platform
Zhiqiang Yang, Dong Liu, Siqing Zeng, Shuixian Yang, Qingming Chen, Zhenshi Chen, Lei Wan, Yan Li
Abstract
An ultra-compact and efficient acousto-optic modulator based on a thin-film lithium niobate-chalcogenide (ChG) hybrid platform was designed and realized. In this approach, π phase-shift Bragg grating has an ultra-short effective interaction length of only ∼ 300 µm and a compact footprint of 200 × 300 µm 2 . The strong microwave-acoustic coupling and superior photo-elastic property of the ChG allow us to achieve a half-wave voltage of V π = 1.08 V (4.07 V) for the π phase-shift Bragg grating (waveguide Bragg grating), corresponding to V π L = 0.03 V·cm (0.09 V·cm). This acousto-optic modulator exhibits a compact size, and low power consumption, and can be used for on-chip optical interconnects and microwave photonics.