Characteristic temperature of a tunneling-injection quantum dot laser

High temperature stability of threshold current has been predicted for the semiconductor quantum dot (QD) laser. An ideal situation would be temperature-insensitive threshold current density j₀ i.e. the characteristic temperature (a widely-accepted figure of merit of any diode laser from the viewpoint of temperature-stability of its y´th) defined as T₀=(partln j_th/partT)^-1. In this paper the authors study the effect of out-tunneling leakage of carriers from QDs and hence of recombination outside QDs on the T-dependence of j₀. The authors show that, even in the presence of such leakage, T₀ remains very high. The authors analyze T₀ versus the parameters of a GalnAsP/InP heterostructure lasing near 1.55 mum.