Abstract
We review methods that enhance the high temperature operation of quantum dot (QD) lasers. First, we
briefly review such conventional methods as p-type doping, the enhancement of carrier confinement in
the ground states of QDs, and increasing the density of the QDs that contribute laser gain. We also review
two recently proposed methods, n-type direct doping and a co-doping technique, both of which resolve
the problem of the high threshold current of p-doped lasers at room temperature. In addition, we
introduce our proposed method that uses lateral potential barrier layers (LPBLs), which enable enhanced
quantum confinement and maintain carrier injection into QDs. We enhanced the temperature stability of
QD lasers with LPBLs.
