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主题:【原创】量子生物学 I 摘要和前言 -- witten1

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家园 相干振动模, quantum beating,量子拍

so, behind "电子激发态之间的强耦合", you have possibly:

1) 无论是实验还是理论工作都有结果明确的提示非微扰及非马尔科夫环境可以同时提高相干时间和激子传输的效率。

2)类似的,一个最近的分析指出相干振动模可能在实验所看到的相干振荡中扮演着重要的角色

3)热浴和不同的BChl分子之间的关联仍然并未被完全理解。最近的工作显示在一些情形,关联确实提升了效率,但在另一些情形又有可能降低,并且应当存在一个最优全局噪声水平

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"类似的,一个最近的分析指出相干"振动模可能在实验所看到的相干振荡中扮演着重要的角色"=kind of quantum beating,量子拍", I would think.

"http://www.pnas.org/content/107/29/12766.full":

For a system of two excitons described by Ψ(t) = c11 + c22....., the time evolution of the density matrix is given by [1]The first two terms represent populations in the excitonic basis, whereas the latter two describe coherences. The phase factors in the coherence terms are responsible for quantum beating, which appears as a periodic modulation of population in the site basis and peak amplitude. The frequency of this beating corresponds to the energy difference between the two excitons giving rise to that particular quantum coherence. Traditionally this phenomenon is ignored in transport dynamics because fast electronic dephasing generally destroys quantum coherence before it can impact the transport process. For example, at cryogenic temperature, coherences between ground and excited states in FMO dephase in approximately 70 fs. In contrast, coherences among excited states have been shown to persist beyond 660 fs—long enough to improve transport efficiency (2). Such a coherence can persist only if the electronic spectral motion among chromophores is strongly correlated, as demonstrated in a conjugated polymer system by Collini and Scholes (20). Biologically, these correlations arise because the protein environment forces transition energies of chromophores to fluctuate together due to spatial uniformity of the dielectric bath. The resultant long-lived quantum coherences evolve in time, creating periodic oscillations in both spectral signals and wave-packet position. This quantum beat provides the signature of quantum coherence

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