NIST scientists develop an 'arbitrary wavelength' laser

NIST researchers have implemented a structure that converts a single laser color into various visible light and infrared wavelengths within an integrated photonics chip.

By 3D-stacking lithium niobate and tantala on a silicon wafer, the chip handles both color conversion of light and electrical control together on a single chip. About 50 fingernail-sized chips, totaling 10,000 photonic circuits, were integrated on a single wafer, with each circuit outputting a different unique wavelength.

The key lies in reducing wavelength constraints. Existing high-quality, compact, high-efficiency lasers worked well only for certain wavelengths, and in fields like quantum clocks and quantum computers, which require specific colors for each atom, equipment with large size, cost, and power consumption was a barrier.

The chip combines two layers of nonlinear materials.

• lithium niobate: electrically controls rapidly turning light on and off and color conversion within the circuit
• tantala: converts a single input laser into the full range of visible light and a wide infrared range

The researchers developed a process to deposit tantala on top of other materials without damage, creating a single chip with different materials 3D-stacked. The experiment also confirmed infrared-to-visible-light conversion operation.

Applications are wide-ranging. Beyond optical atomic clocks and quantum computing, expansion possibilities are mentioned into fields such as AI hardware for chip-to-chip communication and VR displays. However, the current chip is not yet ready for mass production, and scaling up the technology is underway in collaboration with Octave Photonics.