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arXiv · 2104.14451

Like-charge attraction at short distances in a charge-asymmetric two-dimensional two-component plasma: Exact results

Lucas Varela·Gabriel Téllez
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Abstract

We determine exactly the short-distance effective potential between two "guest" charges immersed in a two-dimensional two-component charge-asymmetric plasma composed of positively ($q_1 = +1$) and negatively ($q_2 = -1/2$) charged point particles. The result is valid over the whole regime of stability, where the Coulombic coupling (dimensionless inverse temperature) $β<4$. At high Coulombic coupling $β>2$, this model features like-charge attraction. Also, there cannot be repulsion between opposite-charges at short-distances, at variance with large-distance interactions.

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Lucas Varela, Gabriel Téllez. 2021-04-30. Like-charge attraction at short distances in a charge-asymmetric two-dimensional two-component plasma: Exact results. https://doi.org/10.1088/1742-5468%2Fac1408

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