Complex-valued in-medium potential between heavy impurities in ultracold atoms

• Verfasst von: Akamatsu, Yukinao [VerfasserIn]
• Verfasst von: Endo, Shimpei [VerfasserIn]
• Verfasst von: Fujii, Keisuke [VerfasserIn]
• Verfasst von: Hongo, Masaru [VerfasserIn]
• Titel: Complex-valued in-medium potential between heavy impurities in ultracold atoms
• Verf.angabe: Yukinao Akamatsu, Shimpei Endo, Keisuke Fujii, Masaru Hongo
• E-Jahr: 2024
• Jahr: 3 September, 2024
• Umfang: 14 S.
• Illustrationen: Illustrationen
• Fussnoten: Gesehen am 03.03.2025
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2024
• Band/Heft Quelle: 110(2024), 3, Artikel-ID 033304, Seite 1-14
• ISSN Quelle: 2469-9934
• DOI: doi:10.1103/PhysRevA.110.033304
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1918874336

Abstract

We formulate the induced potential in a finite-temperature cold-atomic medium between two heavy impurities, or polarons, which is shown to be complex valued in general. The imaginary part of the complex-valued potential describes a decoherence effect, and thus the resulting Schrödinger equation for the two polarons acquires a non-Hermitian term. We apply the developed formulation to two representative cases of polarons interacting with medium particles through the ????-wave contact interaction: (i) the normal phase of single-component (i.e., spin-polarized) fermions using the fermionic field theory and (ii) a superfluid phase using the superfluid effective field theory, which is valid either for a Bose-Einstein condensate (BEC) of a single-component Bose gas or for the BEC-BCS crossover in two-component fermions at a low-energy regime. Computing the leading-order term, the imaginary part of the potential in both cases is found to show a universal ????−2 behavior at long distance. We propose three experimental ways to observe the effects of the universal imaginary potential in cold atoms.