Waterlike density anomaly in fermions

Marco A. Habitzreuter; Eduardo O. Rizzatti; Marcia C. Barbosa

doi:10.1016/j.physa.2023.129242

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arXiv · 2306.01161

Waterlike density anomaly in fermions

Marco A. Habitzreuter·Eduardo O. Rizzatti·Marcia C. Barbosa

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Abstract

In this work we explore the one-dimensional extended Hubbard model as a fluid system modelling liquid phases of different densities. This model naturally displays two length scales of interaction, which are connected with waterlike anomalies. We analyze the density anomaly as a function of the model parameters, namely the hopping, on-site and first neighbor interactions. We show that this anomaly is present for a wide range of model parameters and is connected to a ground-state liquid-liquid critical point.

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Marco A. Habitzreuter, Eduardo O. Rizzatti, Marcia C. Barbosa. 2023-06-01. Waterlike density anomaly in fermions. https://doi.org/10.1016/j.physa.2023.129242

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