Electric-Field Behavior of the Resonance Features of the Tunneling Photocurrent Component in InAs(QD)/GaAs Heterostructures

The electric-field behavior of resonance features of the photoelectric characteristics of InAs/GaAs heterostructures is investigated. The emission of carriers excited by light from InAs quantum dots into the GaAs matrix is ​​discussed. It is shown that at the temperature of liquid nitrogen the photocurrent in a strong transverse electric field is only determined by the effect of electron tunneling through a barrier formed at the quantum-dot interfaces. Comparison of the experimental curves with the results obtained using a quasiclassical expression for the tunneling-current component and subsequent analysis of the potential structure made it possible to refine the parameters of the heterostructure under study. The contribution of the resonance component caused by possible electron tunneling through the barrier with the participation of the local defect states to the total tunneling current is analyzed. The influence of the level of excitation of the system on the photocurrent flowing through the InAs/GaAs heterojunction is theoretically studied.