Brueckner $G$-matrix approach to two-dimensional Fermi gases with the finite-range attractive interaction

Hikaru Sakakibara; Hiroyuki Tajima; Haozhao Liang

doi:10.1103/physreva.107.053313

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arXiv · 2302.03446

Brueckner $G$-matrix approach to two-dimensional Fermi gases with the finite-range attractive interaction

Hikaru Sakakibara·Hiroyuki Tajima·Haozhao Liang

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Abstract

Two-dimensional spin-1/2 fermions with the finite-range interaction are theoretically studied. Characterizing the attractive interaction in terms of the scattering length and the effective range, we discuss the finite-range effects on the ground-state properties in this system. The Brueckner $G$-matrix approach is employed to analyze the finite-range effects on an attractive Fermi-polaron energy and the equation of state throughout the BEC-BCS crossover in two dimensions, which can be realized in the population-imbalanced and -balanced cases between two components, respectively. The analytical formulae for these ground states obtained in this study would be useful for understanding many-body phenomena with finite-range interactions in low-dimensional systems.

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Hikaru Sakakibara, Hiroyuki Tajima, Haozhao Liang. 2023-05-19. Brueckner $G$-matrix approach to two-dimensional Fermi gases with the finite-range attractive interaction. https://doi.org/10.1103/physreva.107.053313

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