article published yes Lukas Rammelmüller author David Huber author Matija Čufar author Joachim Brand author Hans-Werner Hammer author Artem Volosniev author 37D278BC-F248-11E8-B48F-1D18A9856A870000-0003-0393-5525 MiLe department We present a numerical analysis of spin-1/2 fermions in a one-dimensional harmonic potential in the presence of a magnetic point-like impurity at the center of the trap. The model represents a few-body analogue of a magnetic impurity in the vicinity of an s-wave superconductor. Already for a few particles we find a ground-state level crossing between sectors with different fermion parities. We interpret this crossing as a few-body precursor of a quantum phase transition, which occurs when the impurity "breaks" a Cooper pair. This picture is further corroborated by analyzing density-density correlations in momentum space. Finally, we discuss how the system may be realized with existing cold-atoms platforms. https://research-explorer.ista.ac.at/download/13278/13328/2023_SciPostPhysics_Rammelmueller.pdf application/pdfno SciPost Foundation2023 eng General Physics and Astronomy 2542-4653 2204.01606 00100032580000810.21468/scipostphys.14.1.006 141 L. Rammelmüller, D. Huber, M. Čufar, J. Brand, H.-W. Hammer, A. Volosniev, SciPost Physics 14 (2023). Rammelmüller L, Huber D, Čufar M, Brand J, Hammer H-W, Volosniev A. 2023. Magnetic impurity in a one-dimensional few-fermion system. SciPost Physics. 14(1), 006. L. Rammelmüller, D. Huber, M. Čufar, J. Brand, H.-W. Hammer, and A. Volosniev, “Magnetic impurity in a one-dimensional few-fermion system,” <i>SciPost Physics</i>, vol. 14, no. 1. SciPost Foundation, 2023. Rammelmüller, L., Huber, D., Čufar, M., Brand, J., Hammer, H.-W., &#38; Volosniev, A. (2023). Magnetic impurity in a one-dimensional few-fermion system. <i>SciPost Physics</i>. SciPost Foundation. <a href="https://doi.org/10.21468/scipostphys.14.1.006">https://doi.org/10.21468/scipostphys.14.1.006</a> Rammelmüller, Lukas, et al. “Magnetic Impurity in a One-Dimensional Few-Fermion System.” <i>SciPost Physics</i>, vol. 14, no. 1, 006, SciPost Foundation, 2023, doi:<a href="https://doi.org/10.21468/scipostphys.14.1.006">10.21468/scipostphys.14.1.006</a>. Rammelmüller L, Huber D, Čufar M, Brand J, Hammer H-W, Volosniev A. Magnetic impurity in a one-dimensional few-fermion system. <i>SciPost Physics</i>. 2023;14(1). doi:<a href="https://doi.org/10.21468/scipostphys.14.1.006">10.21468/scipostphys.14.1.006</a> Rammelmüller, Lukas, David Huber, Matija Čufar, Joachim Brand, Hans-Werner Hammer, and Artem Volosniev. “Magnetic Impurity in a One-Dimensional Few-Fermion System.” <i>SciPost Physics</i>. SciPost Foundation, 2023. <a href="https://doi.org/10.21468/scipostphys.14.1.006">https://doi.org/10.21468/scipostphys.14.1.006</a>. 132782023-07-24T10:48:23Z2023-12-13T11:39:32Z