Abstract

Highly coherent laser diodes (LD′s) are indispensable for studying basic physics (e.g., manipulation of atoms, experiments on P and T violation in atoms, and cavity QED) and for a variety of photonics technology systems. We review here the performances of highly coherent LD′s and their application systems. Two kind of experiments were carried out to reduce linewidth of LD's. In the first experiment, the linewidth of a 1.5-µm-wavelength three-electrode distributed-feedback LD was reduced by using a negative electrical feedback (NEF) loop.

© 1991 Optical Society of America