DISTRIBUTED FEEDBACK TYPE SEMICONDUCTOR LASER CAPABLE OF POLARIZED MODULATION

摘要

PROBLEM TO BE SOLVED: To provide a high-reproducibility distributed feedback type semiconductor laser capable of polarization and a method of using it. SOLUTION: A device has a distributed feedback type semiconductor laser structure having two distributed feedback parts 11a and 11b having different characteristics in the direction to a resonator. The parts 11a and 11b are composed of gain-coupling type diffraction lattice structures 3a and 3b the periods of which are set sot that the Bragg wavelengths of the TE mode and TM mode may agree respectively with peaks of the grain spectra of these modes since the TE and TM modes are dominant in the parts 11a and 11b.