The carrier dynamical issues for extending the operatingwavelength of quantum cascade lasersP
نویسندگان
چکیده
Electron-longitudinal optic phonon and electron-electron intersubband scattering rates are calculated for a variety of quantum well systems. It is demonstrated that the internal quantum eeciency of a Terahertz radiative intersubband transition can be greater than in the mid-infrared at 4 K, however by room temperature has fallen to around 20%. A study of the internal quantum eeciency of a Terahertz energy intersubband transition in double and single quantum wells, has shown that the vertical intrawell transition is more eecient than the diagonal interwell transition.
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