Anomalous breaking of scale invariance in a two-dimensional fermi gas

• Verfasst von: Holten, Marvin [VerfasserIn]
• Verfasst von: Bayha, Luca [VerfasserIn]
• Verfasst von: Klein, Antonia Clara [VerfasserIn]
• Verfasst von: Murthy, Puneet A. [VerfasserIn]
• Verfasst von: Preiss, Philipp [VerfasserIn]
• Verfasst von: Jochim, Selim [VerfasserIn]
• Titel: Anomalous breaking of scale invariance in a two-dimensional fermi gas
• Verf.angabe: M. Holten, L. Bayha, A.C. Klein, P.A. Murthy, P.M. Preiss, and S. Jochim
• E-Jahr: 2018
• Jahr: 17 September 2018
• Umfang: 6 S.
• Fussnoten: Gesehen am 19.11.2019
• Titel Quelle: Enthalten in: Physical review letters
• Ort Quelle: College Park, Md. : APS, 1958
• Jahr Quelle: 2018
• Band/Heft Quelle: 121(2018,12) Artikel-Nummer 120401, 6 Seiten
• ISSN Quelle: 1079-7114
• DOI: doi:10.1103/PhysRevLett.121.120401
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1682138739

Abstract

The frequency of the breathing mode of a two-dimensional Fermi gas with zero-range interactions in a harmonic confinement is fixed by the scale invariance of the Hamiltonian. Scale invariance is broken in the quantized theory by introducing the two-dimensional scattering length as a regulator. This is an example of a quantum anomaly in the field of ultracold atoms and leads to a shift of the frequency of the collective breathing mode of the cloud. In this work, we study this anomalous frequency shift for a two-component Fermi gas in the strongly interacting regime. We measure significant upwards shifts away from the scale-invariant result that show a strong interaction dependence. This observation implies that scale invariance is broken anomalously in the strongly interacting two-dimensional Fermi gas.