Tapered grating effects on static properties of a bistable QWS-DFB semiconductor laser amplifier

Non-uniform Grating Effects On Dynamic Characteristics of Bistable DFB Semiconductor Laser Amplifiers

“…Recently, the effects of trapezoidal tapered gratings on the bistable characteristics of a quarter wavelength phase-shifted DFB-SLA have been analyzed by the authors. The results show that trapezoidal taper widens the spectral range of low-threshold bistable switching and increases the on-off switching contrast [13].…”

“…In this section we demonstrate our numerical results obtained for both steady state and transient conditions. Values of the geometrical and physical parameters used in our numerical analysis are the same as presented in [13].…”

Switching Behavior of Bistable DFB Semiconductor Laser Amplifiers

“…We have already presented the profile of the coupling coefficient calculated for the trapezoidal tapered QWS-DFB of Fig. 1(c), elsewhere [13]. For such a structure, instead of ÄL product used for a non-tapered structure [7] one should use Ä eff L product similar to that presented in [13].…”

“…To account for the bistable behavior of a DFB-SLA, we solve for the gain and intensity distributions using the iterative approach, which is the same as those used by [7,13]. Figure 4 illustrates the bistability curves obtained for uniform, QWS, and trapezoidal tapered grating DFB-SLA's with ıL D 6:75, 1.32, and 0.14, respectively.…”

“…Meanwhile, distorting effects of phase shift and chirp on the falling edge of the output pulse of a bistable DFB-SLA were analyzed by Wu et al [12]. In a most recent report, using transfer matrix method (TMM), Aleshams et al have demonstrated the effects of trapezoidal tapered gratings on the bistable characteristics of a quarter-wavelength phase-shifted DFB-SLA, in which the numerical results have shown that trapezoidal tapering widens the spectral range of low-threshold bistable switching and increases the on-off switching contrast [13].…”