Virginia TechWu, Y. C.Suris, R. A.Asryan, Levon V.2014-04-162014-04-162012-03-01Wu, Yuchang; Suris, Robert A.; Asryan, Levon V., "Effect of internal optical loss on the modulation bandwidth of a quantum dot laser," Appl. Phys. Lett. 100, 131106 (2012); http://dx.doi.org/10.1063/1.36976830003-6951http://hdl.handle.net/10919/47377We show that the internal optical loss, which increases with free-carrier density in the waveguide region, considerably reduces the modulation bandwidth omega(-3 dB) of a quantum dot laser. At a certain optimum value j(0)(opt) of the dc component of the injection current density, the maximum bandwidth omega(max)(-3dB) is attained and the modulation response function becomes as flat as possible. With internal loss cross-section sigma(int) increasing and approaching its maximum tolerable value, omega(max)(-3dB) decreases and becomes zero. As with j(0)(opt), there also exists the optimum cavity length, at which omega(-3 dB) is highest; the larger is sigma(int), the longer is the optimum cavity. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3697683]application/pdfen-USIn CopyrightIntervalence band absorptionConfined active-regionSemiconductor-lasersDiode-lasersWell lasersThresholdPowerGainArticle - Refereedhttp://scitation.aip.org/content/aip/journal/apl/100/13/10.1063/1.3697683https://doi.org/10.1063/1.3697683