We report details of lasing transitions based on self‐localized barrier state electrons in InGaAs/InGaAsP multiple quantum well lasers. We study the mechanisms responsible for the switching between conventional lasing transitions at 1460 nm and a self‐induced transition at 1360 nm. Carrier effects and current heating contribute both on a time scale of a few ns with the current heating dominating. Carrier effects are separable from the thermal effects when 100 ps wide electrical drive pulses are used. ©1996 American Institute of Physics.