Line-Narrowed 1.55microns VPT-DFB Lasers Using Vertically Self-Aligned Si-SiO sub 2 ARROW Cavities
01 January 1986
Recent work has confirmed that stable, narrow-line optical sources can be obtained from a distributed feedback (DFB) semiconductor laser coupled to an external cavity. In such cases the frequency selectivity is provided by the grating of the DFB while the long propagation time in a a low loss medium, either air, an optical fiber, or a GRIN-rod lens, provides the high Q cavity needed for reduced linewidth.