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arXiv · 1811.07810

Measures of electronic-vibrational entanglement and quantum coherence in a molecular system

Mihaela Vatasescu
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Abstract

We characterize both entanglement and quantum coherence in a molecular system by connecting the linear entropy of electronic-nuclear entanglement with Wigner-Yanase skew information measuring vibronic coherence and local quantum uncertainty on electronic energy. Linear entropy of entanglement and quantifiers of quantum coherence are derived for a molecular system described in a bipartite Hilbert space H=Hel x Hvib of finite dimension Nel x Nv, and relations between them are established. For the specific case of the electronic-vibrational entanglement, we find the linear entropy of entanglement as having a more complex informational content than the von Neumann entropy. By keeping the information carried by the vibronic coherences in a molecule, linear entropy seizes vibrational motion in the electronic potentials as entanglement dynamics. We analyze entanglement oscillations in an isolated molecule, and show examples for the control of entanglement dynamics in a molecule through the creation of coherent vibrational wave packets in several electronic potentials by using chirped laser pulses.

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Mihaela Vatasescu. 2018-11-19. Measures of electronic-vibrational entanglement and quantum coherence in a molecular system. https://doi.org/10.1103/physreva.92.042323%3B%2010.1103%2Fphysreva.93.069906

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