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arXiv · 1703.03261

Long- and short-range interaction footprints in entanglement entropies of two-particle Wigner molecules in 2D quantum traps

Eloisa Cuestas·Mariano Garagiola·Federico M. Pont·Omar Osenda·y Pablo Serra
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Abstract

The occupancies and entropic entanglement measures for the ground state of two particles in a two-dimensional harmonic anisotropic trap are studied. We implement a method to study the large interaction strength limit for different short- and long-range interaction potentials that allows to obtain the exact entanglement spectrum and several entropies. We show that for long-range interactions, the von Neumann, min-entropy and the family of Rényi entropies remain finite for the anisotropic traps and diverge logarithmically for the isotropic traps. In the short-range interaction case the entanglement measures diverge for any anisotropic parameter due to the divergence of uncertainty in the momentum since for short-range interactions the relative position width vanishes. We also show that when the reduced density matrix has finite support the Rényi entropies present a non-analytical behaviour.

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Eloisa Cuestas, Mariano Garagiola, Federico M. Pont, Omar Osenda, y Pablo Serra. 2017-03-09. Long- and short-range interaction footprints in entanglement entropies of two-particle Wigner molecules in 2D quantum traps. https://doi.org/10.1016/j.physleta.2017.05.003

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