Arbitrary electro-optic bandwidth and frequency control in lithium niobate optical resonators

TL;DR

This paper demonstrates an in situ tunable optical resonator on lithium niobate, enabling wide-range control over frequency and bandwidth through the linear electro-optic effect, with a predictive model for tuning behavior.

Contribution

It introduces a novel in situ tunable resonator on thin-film lithium niobate with linear electro-optic tuning of frequency and bandwidth, supported by a predictive tuning model.

Findings

Achieved up to 50x bandwidth tuning with ~50 V

Demonstrated linear frequency control of ~230 MHz/V

Developed a closed-form model predicting tuning behavior

Abstract

In situ tunable photonic filters and memories are important for emerging quantum and classical optics technologies. However, most photonic devices have fixed resonances and bandwidths determined at the time of fabrication. Here we present an in situ tunable optical resonator on thin-film lithium niobate. By leveraging the linear electro-optic effect, we demonstrate widely tunable control over resonator frequency and bandwidth on two different devices. We observe up to $\sim50\times$ tuning in the bandwidth over $\sim50$ V with linear frequency control of $\sim230$ MHz/V. We also develop a closed-form model predicting the tuning behavior of the device. This paves the way for rapid phase and amplitude control over light transmitted through our device.