Reconfigurable on-chip optical wireless switches on SiN-TFLN hybrid platform

Integrated optical phased arrays (OPAs) are becoming substantially important in modern integrated photonics because of their fast, precise and non-mechanical beam steering capabilities. In this work, we present a new approach for on-chip communication using a broadband integrated wireless switch, considering a silicon nitride-thin film lithium niobate (SiN-TFLN) hybrid platform. The proposed optical switch is based on OPAs and can address one of the in-plane receivers by properly adjusting the phase shift between the antenna elements comprising the OPA. The precise manufacturing of lithium niobate (LN) components is challenging, due to the nature of complex fabrication processes. The proposed hybrid design circumvents the challenges related to the direct etching of LN components while simultaneously exploiting the advantages of LN. We numerically demonstrate that the optical switch in the hybrid configuration exhibits improved performance as compared to the SiN-only configuration. The phase shifts required for beam steering are achieved using electro-optic effect. We also present the design of a SiN-TFLN electro-optic phase shifter and evaluate the overall energy required to drive the optical switch. We find that the phase shifter demonstrates the half-wave voltage-length product of 4.74 V cm, requiring 5.93 pJ of energy to achieve a phase shift with an interaction region of length less than 1 cm. Moreover, we show that the total energy required by the switch to direct optical signals from transmitter to one of the receivers is 10.52 pJ. Our results demonstrate that this hybrid approach can facilitate the design and realization of integrated photonic devices with enhanced performance.