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.

Influence of an External Electric Field and Dissipative Tunneling on Recombination Radiation in Quantum Dots

“…In the strong dissipation limit for single InAs QDs, taking into account the influence of two local phonon modes on the field dependence of the probability of 1D dissipative tunneling, an oscillating mode with a nonequidistant spectrum of peaks was observed, which qualitatively coincides with the experimental I–V characteristic [ 2 ]. For structures with tunneling photodiodes based on tunneling coupled asymmetric InAs/GaAs quantum molecules, the experimental dependence of the photoconductivity qualitatively corresponded to the field dependence of the probability of 1D dissipative tunneling taking into account the influence of two local phonon modes (longitudinal and transversal optical phonons) [ 4 ].…”

“…Taking into account the results obtained earlier in [1][2][3][4]26], the model Hamiltonian of the system can be written as ( )…”

“…Then the model renormalized 1D potential can be represented in the standard form ( Figure A3 ). Taking into account the results obtained earlier in [ 1 , 2 , 3 , 4 , 26 ], the model Hamiltonian of the system can be written as

Figure A3 Potential energy of a particle along the tunneling coordinate.

where The probability of particle tunneling per unit time can be found in the semiclassical approximation.…”

“…Research in this field, in particular, based on quantum dots with impurity complexes in the external control electric field, is undoubtedly a topical area of research in the field of modern optoelectronics. An important factor that significantly determines the optical response of quantum dots, in addition to the external electric field, is the influence of the surrounding matrix within the framework of the dissipative tunneling mechanism [ 1 , 2 , 3 , 4 ]. When discussing the effect of the surface on the photoluminescence of semiconductor quantum dots during the development of quantum sensors, it was noted [ 5 ] that it is important to take into account as role of recombination radiation as also tunneling mechanism.…”

“…When discussing the effect of the surface on the photoluminescence of semiconductor quantum dots during the development of quantum sensors, it was noted [ 5 ] that it is important to take into account as role of recombination radiation as also tunneling mechanism. Among the possible mechanisms of the quantum dots interaction with the environment (with the heat-bath), we propose to take into account the mechanism of quantum tunneling with dissipation [ 1 , 2 , 3 , 4 ]. In addition, as model parameters of dissipative tunneling, it is necessary to take into account the temperature of the matrix surrounding the quantum dot with the impurity complex “ A + + e ”) in the external control electric field, the parameter of interaction with the contact medium (with the heat-bath), frequencies of optical and acoustic phonon modes of the heat-bath matrix.…”