Abstract
Bilayer InAs/GaAs quantum dot (QD) lasers operating in the excited state at wavelengths that span the O-band are demonstrated. The higher saturated gain and lower scattering time of the excited states of the ensemble of QDs offers the opportunity for fast direct-modulation lasers. We predict an increase in K-factor limited modulation bandwidth from QD lasers operating in the excited state due to a reduction in carrier transport and scattering times whilst maintaining high peak modal gain. (C) 2011 American Institute of Physics. [doi:10.1063/1.3605590]