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arXiv · 0709.3737

The chemical potential for the inhomogeneous electron liquid in terms of its kinetic and potential parts with special consideration of the surface pote ntial step and BCS-BEC crossover

K. Morawetz·N. H. March·R. H. Squire
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Abstract

The chemical potential $μ$ of a many-body system is valuable since it carries fingerprints of phase changes. Here, we summarize results for $μ$ for a thre e-dimensional electron liquid in terms of average kinetic and potential energie s per particle. The difference between $μ$ and the energy per particle is fou nd to be exactly the electrostatic potential step at the surface. We also prese nt calculations for an integrable one-dimensional many-body system with delta f unction interactions, exhibiting a BCS-BEC crossover. It is shown that in the B CS regime the chemical potential can be expressed solely in terms of the ground -state energy per particle. A brief discussion is also included of the strong c oupling BEC limit.

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K. Morawetz, N. H. March, R. H. Squire. 2007-09-24. The chemical potential for the inhomogeneous electron liquid in terms of its kinetic and potential parts with special consideration of the surface pote ntial step and BCS-BEC crossover. https://doi.org/10.1016/j.physleta.2007.10.025

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