6-micron interaction length electro-optic modulation based on lithium niobate photonic crystal cavity.

We report on electro-optic modulation using a Lithium Niobate (LN) Photonic Crystal (PC) cavity structure. The compact device (6 µm in length) consists of a 2D photonic crystal cavity made on an Annealed Proton Exchange (APE) LN waveguide with vertical deposited electrodes. Experimental results show a tunability of 0.6 nm/V. This compact design opens a way towards micro and nano-scale tunable photonic devices with low driving electrical power.

Enhanced electro-optical lithium niobate photonic crystal wire waveguide on a smart-cut thin film.

We report an electro-optically tunable photonic crystal linear cavity etched on a 200 nm lithium niobate waveguide ridge. The photonic crystal cavity and the ridge are both fabricated on a 1 µm thin film of lithium niobate obtained by smart-cut technology. The photonic crystal, of area 4x0.8 µm2, has been engineered to work in a slow light configuration so that the electro-optic effect is 20 times more important than in bulk material.