cw 光注入による半導体ﾚｰｻﾞの全光制御ﾓｰﾄﾞ同期方式におけるｽﾍﾟｸﾄﾙ整形用光ﾌｨﾙﾀ

Abstract

Optical filters, especially band rejection filters, for spectral shaping in all optical mode-locking of semiconductor lasers by cw light injection are studied experimentally. Two types of filters are studied; the ring resonator type and the Mach-Zehnder interferometer type. Active control to compensate for fluctuations of the optical lengths due to the room temperature variation is also studied. The Mach-Zehnder type filters prove to be advantageous because of large variable free spectral ranges and insensitiveness to internal losses. The filter structure and the active control technique are described in detail. These filters are useful for shaping optical spectra both in generation and multiplication/division of high repetition frequency optical pulse trains.