Triplet-singlet relaxation in semiconductor single and double quantum dots

Abstract

We study the triplet-singlet relaxation in two-electron semiconductor quantum dots. Both single dots and vertically coupled double dots are discussed. In our work, the electron-electron Coulomb interaction, which plays an important role in the electronic structure, is included. The spin mixing is caused by spin-orbit coupling which is the key to the triplet-singlet relaxation. We show that the selection rule widely used in the literature is incorrect unless near the crossing/anticrossing point in single quantum dots. The triplet/singlet relaxation in double quantum dots can be markedly changed by varying barrier height, inter-dot distance, external magnetic field and dot size.

7 pages, 4 figures, PRB in press

References in corpus (24)

• Spintronics: Fundamentals and applications
• Quantum Computation with Quantum Dots
• Spins in few-electron quantum dots
• Driven coherent oscillations of a single electron spin in a quantum dot
• Control and Detection of Singlet-Triplet Mixing in a Random Nuclear Field
• Phonon-induced decay of the electron spin in quantum dots
• Zeeman energy and spin relaxation in a one-electron quantum dot
• Nucleus-mediated spin-flip transitions in GaAs quantum dots
• Spin relaxation and anticrossing in quantum dots: Rashba versus Dresselhaus spin-orbit coupling
• Experimental signature of phonon-mediated spin relaxation
• Theory of phonon-induced spin relaxation in laterally coupled quantum dots
• Gate control of spin dynamics in III-V semiconductor quantum dots
• Spin relaxations in semiconductor quantum dots
• Pulsed-gate measurements of the singlet-triplet relaxation time in a two-electron double quantum dot
• Orbital and spin relaxation in single and coupled quantum dots
• Geometrical spin dephasing in quantum dots
• Electrical pump-and-probe study of spin singlet-triplet relaxation in a quantum dot
• Anisotropy of spin splitting and spin relaxation in lateral quantum dots
• Triplet-Singlet Spin Relaxation in Quantum Dots with Spin-Orbit Coupling
• Oscillatory spin relaxation rates in quantum dots
• Effect of electron-electron interaction on the phonon-mediated spin relaxation in quantum dots
• Electric field dependence of spin coherence in (001) GaAs/AlGaAs quantum wells
• Control of spin relaxation in semiconductor double quantum dots
• Dissipative dynamics of spins in quantum dots

Cited by in corpus (19)

• Spin dynamics in semiconductors
• Theory of anisotropic exchange in laterally coupled quantum dots
• Theory of excitons in cubic III-V semiconductor GaAs, InAs and GaN quantum dots: fine structure and spin relaxation
• Tuning of the spin-orbit interaction in a quantum dot by an in-plane magnetic field
• Spin-orbit coupling and anisotropic exchange in two-electron double quantum dots
• Theory of Spin Relaxation in Two-Electron Lateral Coupled Quantum Dots
• Singlet-triplet relaxation in multivalley silicon single quantum dots
• Phonon-induced dephasing of singlet-triplet superpositions in double quantum dots without spin-orbit coupling
• Theory of Spin Relaxation in Two-Electron Lateral Coupled Si/SiGe Quantum Dots
• Singlet-triplet relaxation in SiGe/Si/SiGe double quantum dots
• Singlet-triplet avoided crossings and effective $g$ factor versus spatial orientation of spin-orbit-coupled quantum dots
• Energy spectra of three electrons in Si/SiGe single and vertically coupled double quantum dots
• Coupling of bonding and antibonding electron orbitals in double quantum dots by spin-orbit interaction
• Entanglement dynamics of photon pairs emitted from quantum dot
• Energy spectra of three electrons in SiGe/Si/SiGe laterally coupled triple quantum dots
• Spin-orbit effects on two-electron states in nanowhisker double quantum dots
• Singlet-triplet relaxation induced by confined phonons in nanowire-based quantum dots
• Confinement sensitivity in quantum dot singlet-triplet relaxation
• Non-classical correlation of cascaded photon pairs emitted from quantum dot