Effects of dissipative electron tunneling manifested in the photocurrent of a GaAs p-i-n photodiode with a double InAs quantum dot layer

Abstract

We report on the results of experimental studies of the photocurrent (PC) of photodiodes based on GaAs p-i-n structures with InAs/GaAs(001) double asymmetric quantum dot (DAQD) arrays obtained by self-assembling in the process of low-pressure metal-organic vapor phase epitaxy (LP-MOVPE). Three peaks were observed in the dependence of the PC on the reverse bias, measured under photoexcitation with a photon energy equal to the energy of the interband ground state transition in larger InAs QDs. These peaks were attributed to photoexcitation of electrons from the ground hole states in larger QDs into the ground electron states followed by resonant dissipative (with absorption or emission of optical phonons) and conservative tunneling into the GaAs conduction band via the ground electron states in smaller QDs. The PC dependence on the bias voltage agrees qualitatively with the theoretical field dependence of the probability of 1D dissipative tunneling between the QDs.