High-pressure studies of the recombination processes, threshold currents, and lasing wavelengths in InAs/GaInAs quantum dot lasers

The threshold current of broad area GRINSCH InAs quantum dot (QD) lasers has been measured as a function of hydrostatic pressure in the range of 0-12 kbar. The laser emission photon energy, E-laser, increases linearly with pressure, p, at 10.1 meV/kbar and 8.3 meV/kbar for 980 run and 1.3 mum QD lasers, respectively. For the 980 nm QD lasers the threshold current increases with pressure at a rate proportional to the square of the photon energy, E-laser(2). However, the threshold current of the 1.3 mum QD laser decreases by 26% over a 12 kbar pressure range, demonstrating the importance of the Auger recombination in 1.3 mum QD lasers. The results are discussed in the framework of a theoretical model based on the electronic structure and radiative recombination calculations carried out using an 8 x 8 k (.) p Hamiltonian.