FM response of narrow-linewidth, multielectrode lambda /4 shift DFB laser

Abstract
Flat FM response from 100 kHz to 15 GHz was achieved in a multielectrode distributed-feedback (DFB) laser. A lambda /4-shifted corrugation and a 1200- mu m-long cavity were very effective not only in reducing the linewidth to less than 1 MHz, but also in making FM response flat by selective current injection.