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arXiv · 1601.07197

Dynamics and control of a qubit in spin environment: an exact master equation study

Jun Jing·Lian-Ao Wu
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Abstract

We present an exact master equation for a central spin-$1/2$ system coupled to a spin-$1/2$ bath in terms of hyperfine interaction, which provides a unified formalism for both free evolution and controlled dynamics of the central spin. The equation enables us to study controllability of dynamics processes with various degrees of non-Markovianity. We investigate the Overhauser's effect on decoherence dynamics of the central spin under different bath spectra and the system-bath coupling strengths. Nonperturbative leakage elimination approach is applied to the system to suppress decoherence in solid-state quantum information processing.

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Jun Jing, Lian-Ao Wu. 2016-01-26. Dynamics and control of a qubit in spin environment: an exact master equation study. https://arxiv.org/abs/1601.07197

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