In-situ phase control of a low-loss membrane-based lithium-niobate polarisation-state modulator

Abstract

Abstract: We report on lithium niobate intermediate-thin films with reduced energy-manufacturing costs for manufacturing low-loss electro-optic components. A micrometer-thick membrane surrounded with tapers is inscribed in a single step by smoothly dicing the bottom face of a standard LiNbO3 electro-optic modulator. Hence, we demonstrate a freestanding polarisation-state modulator with insertion losses as low as 2.6 dB. The in-situ structuring of the membrane allows a giant phase control extending over 40°. These developments open the way to a new generation of membrane-based electro-optic devices with low manufacturing-energy costs and reduced yield losses for sensing, telecommunications, or quantum photonics applications.