Abstract
We report the realization of excited state bilayer quantum dot (QD) lasers in the 1.31 mu m region. The higher saturated gain and lower scattering time of the excited states of the ensemble of QDs offers the opportunity for high modulation bandwidths. Gain measurements for these structures are discussed and compared to conventional QD laser structures. The extension of QD ground state operating wavelengths to 1.45 mu m spanning the O- and E-band is also demonstrated. (C) 2011 The Japan Society of Applied Physics