Efficient Electro-optical Tuning of Optical Frequency Microcomb on a Monolithically Integrated High-Q Lithium Niobate Microdisk

TL;DR

This paper presents a highly efficient electro-optical tuning method for a lithium niobate microdisk microcomb, achieving broad spectral coverage and high tuning efficiency on a monolithic integrated platform.

Contribution

The work demonstrates the first monolithic integration of a lithium niobate microdisk microcomb with efficient electro-optical tuning capabilities.

Findings

Spectral bandwidth of microcomb exceeds 200 nm at low pump power.

Electro-optical tuning range of 400 pm with 38 pm/100V efficiency.

High optical Q factor of approximately 7.1 million.

Abstract

We demonstrate efficient tuning of a monolithically integrated lithium niobate microdisk (LN) optical frequency microcomb. Utilizing the high optical quality (Q) factor (i.e., Q~7.1*10^6) of the microdisk, the microcomb spans over a spectral bandwidth of ~200 nm at a pump power as low as 20.4 mW. Combining the large eletro-optic coefficient of LN and optimum design of the geometry of microelectrodes, we demonstrate electro-optical tuning of the comb with a spectral range of 400 pm and a tuning efficiency of ~38 pm/100V.