Light-current characteristic of a quantum well laser with asymmetric barrier layers

Abstract

Light-current characteristic (LCC) of a novel type of quantum well (QW) lasers—QW lasers with asymmetric barrier layers (ABLs)—is studied. The ABLs (one on each side of the QW) prevent electrons from entering the hole-injecting side of the structure and holes from entering the electron-injecting side. The use of ABLs thus suppresses the parasitic electron-hole recombination outside the QW and eliminates the mechanism of sublinearity of the LCC in conventional lasers associated with this recombination and with the carrier capture delay into the QW. As a result, no matter how slow is the carrier capture into the QW, the LCC of an ABL QW laser is virtually linear. In an ABL laser containing indent layers between the QW and each of the ABLs (parasitic recombination still occurs in these thin layers), even in the case of slow capture of carriers into the QW, the LCC is also considerably more linear than in a reference conventional QW laser.