Reduced intermodulation-free dynamic range in gain-lever lasers

Performance analysis of a digital fiber optic link incorporating gain‐levered laser diode transmitter

“…Two‐section laser diode also exhibits optical bistability apart from gain‐levered effect, which is reported earlier . Gain‐levered effect is generally investigated in two‐section laser diode to improve the amplitude modulation efficiency . Modulation depth improvement by gain‐levered mechanism is demonstrated and theoretically explained by Vahala et al It is well known that signal to noise ratio of any communication link depends on modulation depth .…”

“…Optical power variation with injection currents are shown in Figure , for both gain‐levered and unlevered conditions. To obtain the characteristics for the unlevered condition, both the current terminals are shorted together and equal current is given to both regions ( I g = I a ) . To validate our simulation results, the optical power variation with longer section current is calculated for unpumped shorter section ( I a = 0).…”

“…When shorter region current is reduced, the circulating optical power becomes less, which increases the carrier density in the longer section. A sublinear relationship between gain and the carrier density exists in gain‐levered laser, which in turn increases the modulation efficiency …”

Analysis of the effect of optical confinement factor on the distortion performance of gain lever laser diode

“…Improvement in optical modulation depth is also observed in such devices due to gain lever effect [7][8][9][10][11][12][13][14][15]. The inherent nonlinearity of the two section gain lever laser diode also produces harmonic and intermodulation distortion.…”

“…A sublinear relation between optical gain and carrier density is obtained. Hence a small amount of increase in carrier density N g , results in modulation depth improvement in such multi section laser diodes [8][9][10][11][12]. The two sections of laser diode are shorted together as shown in Fig.…”