Title :
Frequency chirping in external modulators
Author :
Koyama, Fumio ; Iga, Kenichi
Author_Institution :
Tokyo Inst. of Technol., Yokohama, Japan
fDate :
1/1/1988 12:00:00 AM
Abstract :
A general formula is given that expresses frequency chirping in some types of external intensity modulators, such as the loss modulator, directional-coupler-type modulator, Mach-Zehnder interferometry-type modulator, and total-internal-reflection-type modulator. The chirping phenomenon treated is caused by the phase modulation due to an accompanied refractive index change. It is uniquely expressed in terms of an α-parameter that contributes to frequency chirping in the same manner as in the direct modulation of a semiconductor laser. In addition, the transmission bandwidth of a single-mode fiber system using an external modulator is discussed and compared with the results obtained utilizing direct laser modulation
Keywords :
electro-optical devices; optical modulation; phase modulation; Mach-Zehnder interferometry-type modulator; chirping phenomenon; direct laser modulation; directional-coupler-type modulator; external intensity modulators; external modulators; frequency chirping; loss modulator; phase modulation; refractive index change; semiconductor laser; single-mode fiber system; total-internal-reflection-type modulator; transmission bandwidth; Bandwidth; Chirp modulation; Fiber lasers; Frequency; Frequency modulation; Intensity modulation; Laser modes; Laser transitions; Optical modulation; Optical reflection; Phase modulation; Power lasers; Refractive index; Semiconductor lasers;
Journal_Title :
Lightwave Technology, Journal of