Non-linear effects on the power dependent photocurrent of self-assembled InAs/GaAs quantum dots

We identify fundamental mechanisms of electron and hole dynamics from self-organized InAs/GaAs quantum dots subject to vertical electric fields by photocurrent and photoluminescence investigations. We observed a nonlinear power dependent photocurrent that is associated with charge accumulation into the dots. Steady-state rate equations have been used to simulate the charge accumulation process. The solution has shown that the charge accumulation should increase the capture rate of electrons into the dots.