Temperature and pressure dependence of the recombination processes in 1.5μm InAs∕InP (311)B quantum dot lasers

The threshold current and its radiative component in 1.5μm InAs∕InP (311)B quantum dot lasers are measured as a function of the temperature. Despite an almost temperature insensitive radiative current, the threshold current increases steeply with temperature leading to a characteristic temperature T0≈55K around 290K. Direct observation of spontaneous emission from the wetting layer shows that some leakage from the dots to the wetting layer occurs in these devices. However, a decrease in the threshold current as a function of pressure is also measured suggesting that Auger recombination dominates the nonradiative current and temperature sensitivity of these devices.