Chip-scale cavity optomechanics in lithium niobate

Abstract

We develop a chip-scale cavity optomechanical system in single-crystal lithium niobate that exhibits high optical quality factors and a large frequency-quality product as high as 3.6 × 1012 Hz at room temperature and atmosphere. The excellent optical and mechanical properties together with the strong optomechanical coupling allow us to efficiently excite the coherent regenerative optomechanical oscillation operating at 375 MHz with a threshold power of 174 μW in the air. The demonstrated lithium niobate optomechanical device enables great potential for achieving electro-optic-mechanical hybrid systems for broad applications in sensing, metrology, and quantum physics.

High‐Q 2D Lithium Niobate Photonic Crystal Slab Nanoresonators

“…It shows a clear cubic dependence on the pump power, an intrinsic signature of third‐harmonic generation. To the best of our knowledge, this is the first time to observe third‐harmonic generation in on‐chip LN nanophotonic devices . The observed THG could contribute from cascaded SHG, direct THG from the third‐order optical nonlinearity, or a combination of these two processes.…”

“…We have demonstrated 2D LN PhC slab nanoresonators with optical Q up to 3.51 × 10 5 that is about three orders of magnitude higher than other 2D LN PhC nanoresonators reported to date . The high optical Q together with tight optical mode confinement results in intriguing nonlinear optical interactions, allowing us to observe both second‐ and third‐harmonic generation . Moreover, the devices exhibit specific polarization of the cavity modes, which enabled us to probe the intriguing anisotropy of nonlinear optical phenomena.…”

“…Lithium niobate (LN), known as “silicon of photonics,” exhibits outstanding electro‐optic, nonlinear optical, acousto‐optic, piezoelectric, photorefractive, pyroelectric, and photoconductive properties, promising for broad applications . The great application potential has attracted significant attention recently to develop LN photonic devices on chip‐scale platforms . However, realizing high‐quality 2D LN PhC structures remains significant challenge, which becomes the major obstacle hindering the exploration of optical phenomena in the nanoscopic scale that would potentially result in intriguing device characteristics and novel functionalities inaccessible by conventional means.…”

Monolithic integration of a lithium niobate microresonator with a free-standing waveguide using femtosecond laser assisted ion beam writing

“…Lithium niobate (LN) microresonators have attracted much attention for their broad range of applications in optical signal processing, quantum electrodynamics and optomechanics123456789. This is mainly due to the excellent material properties of lithium niobate such as a broad transmission window, large nonlinear optical coefficients, and a large electro-optic tunability.…”

“…This is mainly due to the excellent material properties of lithium niobate such as a broad transmission window, large nonlinear optical coefficients, and a large electro-optic tunability. Particularly, the recent advance in the fabrication of high-Q lithium niobate microresonators has promoted the quality factor of such microresonators to 10 5 ~10 6 3456789. This is enabled by patterning a lithium niobate thin film bonded onto 2 μm-thickness SiO 2 with either focused ion beam or reactive ion dry etching35.…”