Decoherence of coupled electron spins via nuclear spin dynamics in quantum dots

Abstract

In double quantum dots, the exchange interaction between two electron spins renormalizes the excitation energy of pair-flips in the nuclear spin bath, which in turn modifies the non-Markovian bath dynamics. As the energy renormalization varies with the Overhauser field mismatch between the quantum dots, the electron singlet-triplet decoherence resulting from the bath dynamics depends on sampling of nuclear spin states from an ensemble, leading to the transition from exponential decoherence in single-sample dynamics to power-law decay under ensemble averaging. In contrast, the decoherence of a single electron spin in one dot is essentially the same for different choices of the nuclear spin configuration.

4 pages 3 figures

References in corpus (7)

• Single-shot read-out of an individual electron spin in a quantum dot
• Fault-Tolerant Quantum Dynamical Decoupling
• Theory of electron spin decoherence by interacting nuclear spins in a quantum dot
• Singlet-triplet decoherence due to nuclear spins in a double quantum dot
• Universal phase shift and non-exponential decay of driven single-spin oscillations
• Universal Scaling of Hyperfine-Induced Electron Spin Echo Decay
• Non-additivity of decoherence rates in superconducting qubits