Under the condition of zero net strain, the effect of high temperature on the optical gain and threshold characteristics and the dependence of the characteristic temperature on the cavity length are analyzed theoretically for InGaAs/InGaAsP strain-compensated multiple quantum well (SCMQW) lasers lattice-matched to InP around 1.55 micrometers wavelength emission. The computed results show that as the temperature increases, both the threshold carrier density and the threshold current density increase. As the cavity length increases, the characteristic temperature increases and the temperature dependence becomes better. The characteristic temperature of a SCMQW laser is higher than that of a strain-compensated single quantum well (SCSQW) laser. Therefore, the temperature dependence of the SCMQW laser is better than that of the SCSQW laser. In addition, we find that in order to always keep 1.55 micrometers wavelength emission, certain relations exist among the well width, cavity length and temperature.
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