Abstract

The electroabsorption modulator-integrated distributed-feedback (MI-DFB) laser diode (LD) is attractive for use in high-speed , long-haul optical-fiber transmission systems because of its low-chirp characteristic.¹ Ideally, an MI-DFB laser has the same frequency chirp as a solitary electroabsorption modulator. However, due to residual reflection at the output facet, feedback light interacting with the laser causes excess chirp.² The excess chirp increases the bit-error-rate penalty in highdispersion systems, which are sensitive to both the amount and the form of the chirp. Therefore, it is important to evaluate the time-resolved dynamic chirp of MI-DFB lasers.

© 1995 Optical Society of America