Dependence of threshold current on QW position and on pressure in 1.5 mu mInGaAs(P) lasers

The threshold current has been measured as a function of pressure for a ser ies of 1.5 mu m InGaAs(P) lasers in which the position of the quantum wells (QWs) has been varied within the active region. Devices with the QWs posit ioned towards the p-doped cladding layer exhibit both a lower threshold cur rent density and a reduced pressure dependence of the threshold current com pared to devices with the QWs placed either symmetrically between the cladd ing layers or towards the n-doped cladding layer. Monte-Carlo simulations o f the trajectories of Auger-generated hot carriers show that the escape pro bability of hot holes depends considerably more strongly on the QW position than is the case for hot electrons. The combination of the experimental me asurements and Monte-Carlo simulations demonstrates the importance of Auger recombination processes which result in the production of hot holes.