Measurement, control, and decay of quantum-dot spins

Abstract

In this review we discuss a recent proposal to perform partial Bell-state (parity) measurements on two-electron spin states for electrons confined to quantum dots. The realization of this proposal would allow for a physical implementation of measurement-based quantum computing. In addition, we consider the primary sources of energy relaxation and decoherence which provide the ultimate limit to all proposals for quantum information processing using electron spins in quantum dots. We give an account of the Hamiltonians used for the most important interactions (spin-orbit and hyperfine) and survey some of the recent work done to understand dynamics, control, and decoherence under the action of these Hamiltonians. We conclude the review with a table of important decay times found in experiment, and relate these time scales to the potential viability of measurement-based quantum computing.

v1: 15 pages, 1 figure, review article to be published in a special issue of physica status solidi (b); v2: added/updated citation list, decay times in Table 1, made other minor corrections

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Cited by in corpus (10)

• Performance of Deterministic Dynamical Decoupling Schemes: Concatenated and Periodic Pulse Sequences
• Observation of extremely slow hole spin relaxation in self-assembled quantum dots
• Entangling spins by measuring charge: a parity-gate toolbox
• Robust manipulation of electron spin coherence in an ensemble of singly charged quantum dots
• Geometric phases in semiconductor spin qubits: Manipulations and decoherence
• Triplet-Singlet Spin Relaxation in Quantum Dots with Spin-Orbit Coupling
• Quantum versus classical hyperfine-induced dynamics in a quantum dot
• Generalized parity measurements
• Spin dephasing due to a random Berry phase
• The quadrupole mechanism of hole spin relaxation