Title :
Multigigahertz bandwidth FM response of frequency tunable two-electrode DFB lasers
Author :
Willner, A.E. ; Kuznetsov, M. ; Kaminow, I.P. ; Koren, U. ; Koch, T.L. ; Burrus, C.A. ; Raybon, G.
Author_Institution :
AT&T Bell Lab., Holmdel, NJ, USA
Abstract :
The FM response of frequency-tunable two-electrode distributed-feedback (DFB) lasers operating at 1.35 mu m is discussed. Under certain bias conditions, an FM response of approximately 1 GHz/mA is flat over a range of modulating frequencies from 10 kHz to several hundred megahertz. This region is followed by a shallow dip and a high-frequency relaxation resonance peak, allowing an overall 3-dB FM bandwidth of approximately 5 GHz. This is believed to be the widest FM bandwidth reported to date for such lasers; however, variations of the phase of the FM response could limit the useful bandwidth in a frequency-shift keying (FSK) system. The experimental response is a function of static tuning conditions, with significant differences between regions of red and blue frequency shift with increasing current. The observed behavior is well represented by theoretical curves derived from a small-signal analysis.<>
Keywords :
distributed feedback lasers; frequency modulation; frequency shift keying; optical modulation; semiconductor junction lasers; 1.35 micron; 5 GHz; InGaAsP-InP; bias conditions; blue frequency shift; frequency shift keying system; frequency tunable two-electrode DFB lasers; frequency-tunable two-electrode distributed-feedback; high-frequency relaxation resonance peak; modulating frequencies; multigigahertz bandwidth FM response; red frequency shift; shallow dip; small-signal analysis; static tuning conditions; theoretical curves derived; Bandwidth; Chemical lasers; Distributed Bragg reflectors; Frequency modulation; Frequency shift keying; Laser theory; Laser tuning; Resonance; Semiconductor lasers; Tunable circuits and devices;
Journal_Title :
Photonics Technology Letters, IEEE
