Phonon-assisted relaxation and tunneling in self-assembled quantum dot molecules

TY - JOUR

T1 - Phonon-assisted relaxation and tunneling in self-assembled quantum dot molecules

AU - Gawarecki, Krzysztof

AU - Pochwala, Michal

AU - Grodecka-Grad, Anna

AU - Machnikowski, Pawel

PY - 2010/6/14

Y1 - 2010/6/14

N2 - We study theoretically phonon-assisted relaxation processes in a system consisting of one or two electrons confined in two vertically stacked self-assembled quantum dots. The calculation is based on a kp approximation for single-particle wave functions in a strained self-assembled structure. From these, two-particle states are calculated by including the Coulomb interaction and the transition rates between the lowest-energy eigenstates are derived. We take into account phonon couplings via deformation potential and piezoelectric interaction and show that they both can play a dominant role in different parameter regimes. Within the Fermi golden rule approximation, we calculate the relaxation rates between the lowest-energy eigenstates which lead to thermalization on a picosecond time scale in a narrow range of dot sizes.

AB - We study theoretically phonon-assisted relaxation processes in a system consisting of one or two electrons confined in two vertically stacked self-assembled quantum dots. The calculation is based on a kp approximation for single-particle wave functions in a strained self-assembled structure. From these, two-particle states are calculated by including the Coulomb interaction and the transition rates between the lowest-energy eigenstates are derived. We take into account phonon couplings via deformation potential and piezoelectric interaction and show that they both can play a dominant role in different parameter regimes. Within the Fermi golden rule approximation, we calculate the relaxation rates between the lowest-energy eigenstates which lead to thermalization on a picosecond time scale in a narrow range of dot sizes.

U2 - 10.1103/PhysRevB.81.245312

DO - 10.1103/PhysRevB.81.245312

M3 - Journal article

SN - 2469-9950

VL - 81

SP - 245312

JO - Physical Review B

JF - Physical Review B

IS - 24

ER -