Physics

Laser linewidth

Laser

Optics

Semiconductor laser theory

Semiconductor

Metrology

Materials science

Coherence (philosophical gambling strategy)

Silicon

Quantum mechanics

Tunable laser

Optoelectronics

APL Photonics

Narrow linewidth lasers have many applications, such as higher order coherent communications, optical sensing, and metrology. While semiconductor lasers are typically unsuitable for such applications due to relatively low coherence, recent advances in heterogeneous integration of III-V with silicon have shown that this is no longer true. In this tutorial, we discuss in-depth techniques that are used to drastically reduce the linewidth of a laser. The heterogeneous silicon-III/V platform can fully utilize these techniques, and fully integrated lasers with Lorentzian linewidth on the order of 100 Hz and tuning range of 120 nm are shown.

Tutorial on narrow linewidth tunable semiconductor lasers using Si/III-V heterogeneous integration