Ultraviolet

Materials science

Telecommunications

Computer science

Wavelength

Diode

Photonics

Laser

Physics

Laser linewidth

Optics

Resonator

Tunable laser

Chip

Semiconductor laser theory

Optoelectronics

Nature Photonics

Widely tunable and narrow-linewidth lasers at visible wavelengths are necessary for applications such as quantum optics, optical clocks and atomic and molecular physics. At present, the lasers are benchtop systems, which precludes these technologies from being used outside research laboratories. Here we demonstrate a chip-scale visible laser platform that enables tunable and narrow-linewidth lasers from near-ultraviolet to near-infrared wavelengths. Using micrometre-scale silicon nitride resonators and commercial Fabry–Pérot laser diodes, we achieve coarse tuning up to 12.5 nm and mode-hop-free fine tuning up to 33.9 GHz with intrinsic linewidths down to a few kilohertz. In addition, we show fine-tuning speeds of up to 267 GHz µs−1, fibre-coupled powers of up to 10 mW and typical side-mode suppression ratios above 35 dB. These specifications of our chip-scale lasers have only been achieved previously using large state-of-the-art benchtop laser systems, making our lasers stand out as powerful tools for the next generation of visible-light technologies. A chip-scale laser platform based on silicon nitride ring resonators and commercial Fabry–Pérot laser diodes is developed for the wavelength range from 404 nm to 785 nm. The achieved coarse and fine tunings are up to 12.5 nm and 33.9 GHz, respectively, with kilohertz-scale linewidths and side-mode suppression ratios above 35 dB.

Widely tunable and narrow-linewidth chip-scale lasers from near-ultraviolet to near-infrared wavelengths