Finite-range effects in the two-dimensional repulsive Fermi polaron
Abstract
We study the repulsive Fermi polaron in a two-component, two-dimensional system of fermionic atoms inspired by the results of a recent experiment with Yb atoms [N. Darkwah Oppong \textit{et al.}, Phys. Rev. Lett. \textbf{122}, 193604 (2019)]. We use the diffusion Monte Carlo method to report properties such as the polaron energy and the quasi-particle residue that have been measured in that experiment. To provide insight on the quasi-particle character of the problem, we also report results for the effective mass. We show that the effective range, together with the scattering length, is needed in order to reproduce the experimental results. Using different model potentials for the interaction between the Fermi sea and the impurity, we show that it is possible to establish a regime of universality, in terms of these two parameters, that includes the whole experimental regime. This illustrates the relevance of quantum fluctuations and beyond mean-field effects to correctly describe the Fermi polaron problem.
Cite
@article{arxiv.2008.10510,
title = {Finite-range effects in the two-dimensional repulsive Fermi polaron},
author = {Raúl Bombín and Viktor Cikojević and Juan Sánchez-Baena and Jordi Boronat},
journal= {arXiv preprint arXiv:2008.10510},
year = {2021}
}