Two-Timescale Photonic Chips Forge New Colors On Demand

Researchers at JQI designed a chip consisting of an array of resonators that exploit two distinct light-circulation timescales to passively satisfy frequency-phase matching, enabling second-, third-, and fourth-harmonic generation from a 190 THz input without active tuning. The on-chip generation of new colors (red, green, blue) eliminates the need for additional lasers or heaters and could impact metrology and nonlinear optical computing by providing compact, scalable light sources.