Widely-tunable optical parametric oscillator in lithium niobate nanophotonics

Abstract

Widely-tunable coherent sources in nanophotonics are desirable for a multitude of applications ranging from communications to sensing. The mid-infrared spectral region (wavelengths beyond 2 μm) is particularly important for applications relying on molecular spectroscopy. Among tunable sources, optical parametric oscillators typically offer some of the broadest tuning ranges; however, their implementations in nanophotonics have been limited to modest tuning ranges and only at visible and near-infrared wavelengths. Here, we surpass these limits by demonstrating octave-spanning tunable optical parametric oscillators in dispersion-engineered periodically-poled lithium niobate nanophotonics. With a pump wavelength near 1 μm, we generate output wavelengths tunable from 1.53 μm to 3.25 μm, including common telecommunication bands and into the mid-infrared. Our results enable opportunities for numerous integrated photonic applications requiring compact tunable sources.