Weak measurement of quantum dot spin qubits

Abstract

The theory of weak quantum measurements is developed for quantum dot spin qubits. Building on recent experiments, we propose a control cycle to prepare, manipulate, weakly measure, and perform quantum state tomography. This is accomplished using a combination of the physics of electron spin resonance, spin blockade, and Coulomb blockade, resulting in a charge transport process. We investigate the influence of the surrounding nuclear spin environment, and find a regime where this environment significantly simplifies the dynamics of the weak measurement process, making this theoretical proposal realistic with existing experimental technology. We further consider spin-echo refocusing to combat dephasing, as well as discuss a realization of "quantum undemolition", whereby the effects of quantum state disturbance are undone.

8 pages, 2 figures

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Cited by in corpus (8)

• Weak values of electron spin in a double quantum dot
• Uncollapsing the wavefunction by undoing quantum measurements
• Conditioned spin and charge dynamics of a single electron quantum dot
• Protective measurement of open quantum systems
• Optimal nonlinear filtering of quantum state
• Spatio-Temporal Weak Measurement of Chiral Ultra short Laser Pulse
• Uncollapsing the wavefunction
• Time Derivatives of Weak Values