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Mutual information and electron correlation in momentum space.
Robin P Sagar1, Nicolais L Guevara
1Departamento de Química, Universidad Autónoma Metropolitana Apartado Postal 55-534, Iztapalapa, 09340 México D.F., México.
The Journal of Chemical Physics
|April 15, 2006
Summary
Mutual information in momentum space quantifies nonlocal information. For helium isoelectronic series, triplet states show spatial and momentum correlations controlled by electronic correlation strength.
Area of Science:
- Quantum information theory
- Atomic physics
Background:
- Mutual information and information entropies are key measures in quantum information.
- Understanding nonlocal correlations is crucial in quantum systems.
Purpose of the Study:
- To propose mutual information and information entropies in momentum space as measures of nonlocal information.
- To examine Coulomb and Fermi correlations in helium isoelectronic series using these measures.
Main Methods:
- Analysis of singlet and triplet states of helium isoelectronic series.
- Calculation of mutual information and Shannon entropies in both position and momentum spaces.
Main Results:
- Triplet state measures demonstrate that spatial correlations relative to momentum correlations are controllable by electronic correlation strength.
- Shannon entropies in triplet states reveal a crossover point with localized momentum density.
- Momentum space mutual information density indicates strong correlation at small momentum values (p) at this crossover.
Conclusions:
- Mutual information in momentum space effectively captures nonlocal aspects of quantum information.
- Electronic correlation strength plays a significant role in modulating spatial and momentum correlations.
- A localized momentum density signifies strong correlation in momentum space for specific electronic configurations.
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