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

Abstract

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 k.p 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.

arXiv comment13 pages, 10 figures; moderately modified, some new dscussion (including 1 new figure)

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Cited by in corpus (23)

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• The role of phonons for exciton and biexciton generation in an optically driven quantum dot
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• Electron states in a double quantum dot with broken axial symmetry
• Phonon-assisted relaxation between hole states in quantum dot molecules
• Excitons in quantum dot molecules: Coulomb coupling, spin-orbit effects and phonon-induced line broadening
• Dark Exciton Preparation in a Quantum Dot by a Longitudinal Light Field Tuned to Higher Exciton States
• Phonon-assisted tunnelling of electrons in a quantum well-quantum dot injection structure
• Controllable electron spin dephasing due to phonon state distinguishability in a coupled quantum dot system
• Entanglement Dynamics of Molecular Exciton States in Coupled Quantum Dots
• Tunneling-related electron spin relaxation in self-assembled quantum-dot molecules
• Decay and persistence of spatial coherence during phonon-assisted relaxation in double quantum dots
• Intraband absorption in finite, inhomogeneous quantum dot stacks for intermediate band solar cells: limitations and optimization
• Polaron resonances in two vertically stacked quantum dots
• Spectral broadening of optical transitions at tunneling resonances in InAs/GaAs coupled quantum dot pairs
• Phonon-assisted carrier tunneling in coupled quantum dot systems with hyperfine-induced spin flip
• Double quantum dot in a quantum dash: optical properties
• Enhanced solar photocurrent using a quantum dot molecule
• Spin-orbit-induced hole spin relaxation in a quantum dot molecule: the effect of $s$-$p$ coupling
• Gate-based protocol simulations for quantum repeaters using quantum-dot molecules in switchable electric fields
• Single-particle and collective excitations in quantum wires comprised of vertically stacked quantum dots: Finite magnetic field
• Intermediate band formation and intraband absorption for electrons in an inhomogeneous chain of quantum dots