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arXiv · 1709.02512

Protecting coherence by reservoir engineering: intense bath disturbance

Zixian Zhou·Zhiguo Lü·Hang Zheng
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Abstract

We put forward a scheme based on reservoir engineering to protect quantum coherence from leaking to bath, in which we intensely disturb the Lorentzian bath by N harmonic oscillators. We show that the intense disturbance changes the spectrum of the bath and reduces the qubit-bath interaction. Furthermore, we give the exact time evolution with the Lorentzian spectrum by a master equation, and calculate the concurrence and survival probability of the qubits to demonstrate the effect of the intense bath disturbance on the protection of coherence. Meanwhile, we reveal the dynamic effects of counter-rotating interaction on the qubits as compared to the results of the rotating wave approximation.

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Zixian Zhou, Zhiguo Lü, Hang Zheng. 2017-09-08. Protecting coherence by reservoir engineering: intense bath disturbance. https://doi.org/10.1007/s11128-016-1327-7

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