Statistical Interaction Description of Pauli Crystals in 2D Systems of Harmonically Confined Fermions
It is conjectured that the Pauli exclusion principle alone may be responsible for a particular geometric arrangement of confined systems of identical fermions even when there is no interaction between them. These geometric structures, called Pauli crystals, are predicted for a two-dimensional (2D) system of free fermions under harmonic confinement. In this work, the possibility of this outcome is pursued and a theoretical model is considered that may capture both qualitatively and quantitatively, the key features of the abovementioned setup. The results for (Formula presented.) and 6 particles show that the minimum energy configuration corresponds to and is in good quantitative agreement with the reported values of Pauli crystals seen in single-shot imaging data obtained via the configuration density technique. Numerical results for larger systems of (Formula presented.) and 30 particles show that the crystalline configurations observed are not the same as the classical Wigner crystal structures that emerge should the confined charged particles interact with a Coulomb potential. An important question floated is whether such crystalline structures do really exist in a quantum system or whether they are artifacts of the methods used to analyze them.
Ciftja, O., & Batle, J. (2019). Statistical Interaction Description of Pauli Crystals in 2D Systems of Harmonically Confined Fermions. Retrieved from https://digitalcommons.pvamu.edu/chemistry-physics-facpubs/163