Experimental investigation of the impact of optical injection on vital parameters of a gain-switched pulse source

Abstract

An analysis of optical injection on a gain-switched DFB laser and its impact on pulse parameters that influence the performance of the pulse source in high-speed optical communication systems is presented in this paper. A range of 10 GHz in detuning and 5 dB in injected power has been experimentally identified to attain pulses, from an the optically injected gain-switched DFB laser, with durations below 10 ps and pedestal suppression higher than 35 dB. These pulse features are associated with an SMSR of about 30 dB and a timing jitter of less than 1 ps. This demonstrates the feasibility of using optical injection in conjunction with appropriate pulse compression schemes for developing an optimized and cost-efficient pulse source, based on a gain-switched DFB laser, for high-speed photonic systems.

Optical injection-induced timing jitter reduction in gain-switched single-mode vertical-cavity surface-emitting lasers

“…Fig. 4 shows that, as previously reported in DFB lasers [9], optical injection produces a narrowing of the optical spectrum and an improvement of the side mode suppression ratio of 23 dB. Output power (dBm)…”

“…Short optical pulses with small timing jitter are desirable as data signals in high-frequency optical communication systems. Timing jitter reduction has been achieved by using optical injection in gain-switched DFB lasers [8]- [9]. A similar study has been recently considered in VCSELs in a theoretical way [10].…”

Experimental study of optical frequency comb generation in gain-switching vertical-cavity surface-emitting laser driven by various modulation signals under optical injection

“…OFC has attracted much attention due to its extensive applications in metrology, atomic clock, terahertz generation, optical communications, and other fields [1][2][3][4][5] . At present, several techniques have been used to generate OFC in laser diodes, for example, mode locking, electro-optical modulation, micro-ring resonance and gain-switching [6][7][8][9][10][11][12] . Gain-switching consists in driving the semiconductor laser to produce a regular pulse train by the radio frequency (RF) large signal modulation, where the RF signal is usually sinusoidal and superimposed on a direct bias current 13,14 .…”