Title :
Performance improvements in high-frequency modulation of a laser diode under enhanced optical feedback
Author :
Chan, N.H. ; Shu, C. ; Lee, K.L.
Author_Institution :
Dept. of Electron. Eng., Chinese Univ. of Hong Kong, Shatin, China
Abstract :
Improvement in the high-frequency modulation characteristics of a Fabry-Perot laser diode has been observed when the device is driven in an external cavity that provides an amplified optical feedback. At a driving frequency of 10 GHz, the weak sinusoidal waveform in the original output is turned into a train of narrow pulses with a width of 23 ps. Under an optimized feedback level, an improvement of 15.4 dB in the electrical modulation efficiency and 21.2 dB in the sidemode suppression ratio are observed. The output pulses also exhibit a reduced chirp with a minimized total root-mean square noise.
Keywords :
laser cavity resonators; laser feedback; laser noise; optical modulation; phase noise; semiconductor lasers; 10 GHz; Fabry-Perot laser diode; SSB noise spectra; amplified optical feedback; driving frequency; electrical modulation efficiency; enhanced optical feedback; external cavity driven laser; high-frequency modulation; minimized total root-mean square noise; narrow pulse train; optimized feedback level; reduced chirp; sidemode suppression ratio; weak sinusoidal waveform; Diode lasers; Distributed feedback devices; Erbium-doped fiber amplifier; Laser feedback; Laser modes; Laser noise; Optical feedback; Optical noise; Optical pulses; Pulse width modulation;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2002.804645
