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arXiv · 0707.0725

Quantum dynamics of a qubit coupled with structured bath

Peihao Huang·H. Zheng
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Abstract

The dynamics of an unbiased spin-boson model with Lorentzian spectral density is investigated theoretically in terms of the perturbation theory based on a unitary transformation. The non-equilibrium correlation function $P(t)$ and susceptibility $χ^{\prime\prime}(ω)$ are calculated for both the off-resonance case $Δ\lesssim 0.5Ω$ and the on-resonance case $Δ\sim Ω$. The approach is checked by the Shiba's relation and the sum rule. Besides, the coherent-incoherent transition point $α_c$ can be determined, which has not been demonstrated for the structured bath by previous authors up to our knowledge.

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Peihao Huang, H. Zheng. 2007-10-26. Quantum dynamics of a qubit coupled with structured bath. https://doi.org/10.1088/0953-8984%2F20%2F39%2F395233

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