Dynamical control of electron spin coherence in a quantum dot

Abstract

We investigate the performance of dynamical decoupling methods at suppressing electron spin decoherence from a low-temperature nuclear spin reservoir in a quantum dot. The controlled dynamics is studied through exact numerical simulation, with emphasis on realistic pulse delays and long-time limit. Our results show that optimal performance for this system is attained by a periodic protocol exploiting concatenated design, with control rates substantially slower than expected from the upper spectral cutoff of the bath. For a known initial electron spin state, coherence can saturate at long times, signaling the creation of a stable ``spin-locked'' decoherence-free subspace. Analytical insight on saturation is obtained for a simple echo protocol, in good agreement with numerical results.

4 pages, 4 figures with 3 of them in color

References in corpus (11)

• Driven coherent oscillations of a single electron spin in a quantum dot
• Fault-Tolerant Quantum Dynamical Decoupling
• Theory of electron spin decoherence by interacting nuclear spins in a quantum dot
• Optical control of spin coherence in singly charged (In,Ga)As/GaAs quantum dots
• Restoring Coherence Lost to a Slow Interacting Mesoscopic Bath
• Coherence Time of a Solid-State Nuclear Qubit
• Hyperfine interaction induced decoherence of electron spins in quantum dots
• Enhanced Convergence and Robust Performance of Randomized Dynamical Decoupling
• Universal Scaling of Hyperfine-Induced Electron Spin Echo Decay
• Controlling quantum systems by embedded dynamical decoupling schemes
• Optically-controlled single-qubit rotations in self-assembled InAs quantum dots

Cited by in corpus (10)

• Decoherence, Entanglement and Irreversibility in Quantum Dynamical Systems with Few Degrees of Freedom
• Universality of Uhrig dynamical decoupling for suppressing qubit pure dephasing and relaxation
• Pure quantum dephasing of a solid state electron spin qubit in a large nuclear spin bath coupled by long-range hyperfine-mediated interactions
• Nuclear Spins in Nanostructures
• Dynamical Quantum Error Correction of Unitary Operations with Bounded Controls
• Concatenated dynamical decoupling in a solid-state spin bath
• Long-time electron spin storage via dynamical suppression of hyperfine-induced decoherence in a quantum dot
• Bang-Bang control of a qubit coupled to a quantum critical spin bath
• Advantages of Randomization in Coherent Quantum Dynamical Control
• Spin echo without an external permanent magnetic field