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arXiv · 1903.08499

Level crossings and Fisher information of two hard-core bosons in a two-dimensional trap

Dimitris Saraidaris·Ioannis Mitrakos·Ioannis Brouzos·Fotios Diakonos
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Abstract

We investigate a two-body quantum system with hard-core interaction potential in a two-dimensional harmonic trap. We provide the exact analytical solution of the problem. The energy spectrum of this system as a function of the range of the interaction reveals level crossings which can be explained examining the potential and kinetic part of the energy, as well as the localization and oscillatory properties of the wavefunctions quantified by the Fisher information. The latter is sensitive to the wavefunction localization between nodes promoting this property as a resource of quantum correlations in interacting particle systems.

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Dimitris Saraidaris, Ioannis Mitrakos, Ioannis Brouzos, Fotios Diakonos. 2019-03-20. Level crossings and Fisher information of two hard-core bosons in a two-dimensional trap. https://arxiv.org/abs/1903.08499

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