Overview
- Caltech reports the results in Nature Photonics in a paper led by Ryoto Sekine titled “Multi‑Octave Frequency Comb from an Ultra‑Low‑Threshold Nanophotonic Parametric Oscillator.”
- The chip‑scale device generates an evenly spaced, stable comb spanning visible to mid‑infrared wavelengths using input energies in the femtojoule range.
- Performance stems from dispersion engineering and a carefully designed resonator implemented in lithium niobate on a nanophotonic platform.
- Experiments revealed coherence reestablishes when the oscillator is driven far above threshold, contradicting prior textbook expectations and simulations.
- The advance lowers a key energy bottleneck for on‑chip frequency combs and points to applications in spectroscopy, communications, atomic clocks, and molecular sensing.