Characterizations of multi-segment DFB laser

Abstract

Tunable semiconductor laser has various applications including Wavelength Division Multiplexing (WDM), Frequency Division Multiplexing (FDM), optical switching in Local Area Networks (LAN) and Chemical Sensing, or Spectroscopy. There are different approaches for tunable semiconductor lasers. Large wavelength tuning range is required for communication applications, such as WDM. Whereas a frequency modulation (FM) requires small but fast frequency shifts. Two-Segment laser is one of the methods to realize continuous optical tuning. The device consists of two coupled cavities having a series of well-defined modes. The modes are equally spaced within a cavity but the mode spacing between the two cavities is slightly different. Characterization results of such lasers are very important. In this paper we will present the characterization results of two segment InGaAs/InP distributed feed back (DFB) tunable lasers.