Caltech chip creates ultra-efficient light spectrum across wide range

A Caltech research team led by Professor Alireza Marandi has developed a groundbreaking chip-based optical parametric oscillator (OPO) that generates stable, coherent laser light across an exceptionally broad spectrum, ranging from visible to mid-infrared wavelengths. Unlike traditional bulky and power-intensive OPO systems, this nanophotonic device operates at ultra-low energy levels (femtojoule range) and produces a frequency comb—a set of evenly spaced laser lines used for ultra-precise measurements—on a compact chip. This advancement addresses longstanding challenges of size, tunability, and energy consumption in frequency comb technology. The key innovation lies in the device’s dispersion engineering and resonator design, which enable it to maintain coherence while broadening the spectrum even at power levels well above the oscillation threshold. This new operational regime defies conventional understanding of OPO behavior and allows for unprecedented spectral broadening with high efficiency. The technology promises to accelerate applications in precision spectroscopy, atomic clocks, molecular sensing,