Anisotropic Harper-Hofstadter-Mott model: Competition between condensation and magnetic fields

Hügel, Dario; Strand, Hugo U. R.; Werner, Philipp und Pollet, Lode (2017): Anisotropic Harper-Hofstadter-Mott model: Competition between condensation and magnetic fields. In: Physical Review B, Bd. 96, Nr. 5, 54431

Abstract

We derive the reciprocal clustermean-fieldmethod to study the strongly interacting bosonic Harper-Hofstadter-Mott model. The system exhibits a rich phase diagram featuring band insulating, striped superfluid, and supersolid phases. Furthermore, for finite hopping anisotropy, we observe gapless uncondensed liquid phases at integer fillings, which are analyzed by exact diagonalization. The liquid phases at fillings nu = 1,3 exhibit the same band fillings as the fermionic integer quantum Hall effect, while the phase at nu = 2 is CT-symmetric with zero charge response. We discuss how these phases become gapped on a quasi-one-dimensional cylinder, leading to a quantized Hall response, which we characterize by introducing a suitable measure for nontrivial many-body topological properties. Incompressible metastable states at fractional filling are also observed, indicating competing fractional quantum Hall phases. The combination of reciprocal cluster mean-field and exact diagonalization yields a promising method to analyze the properties of bosonic lattice systems with nontrivial unit cells in the thermodynamic limit.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Fakultätsübergreifende Einrichtungen: Center for NanoScience (CENS)
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik ; 500 Naturwissenschaften und Mathematik > 500 Naturwissenschaften
• ISSN: 2469-9950
• Sprache: Englisch