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arXiv · 1508.04622

Quantum speed-up of multiqubit open system via dynamical decoupling pulses

Ya-Ju Song·Qing-Shou Tan·Le-Man Kuang
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Abstract

We present a method to accelerate the dynamical evolution of multiqubit open system by employing dynamical decoupling pulses (DDPs) when the qubits are initially in W-type states. It is found that this speed-up evolution can be achieved in both of the weak-coupling regime and the strong-coupling regime. The physical mechanism behind the acceleration evolution is explained as the result of the joint action of the non-Markovianity of reservoirs and the excited-state population of qubits. It is shown that both of the non-Markovianity and the excited-state population can be controlled by DDPs to realize the quantum speed-up.

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Ya-Ju Song, Qing-Shou Tan, Le-Man Kuang. 2015-08-19. Quantum speed-up of multiqubit open system via dynamical decoupling pulses. https://arxiv.org/abs/1508.04622

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