Year: 2018
Type: article
Abstract: We investigate topological charge pumping in a system of interacting bosons in the tight-binding limit, described by the Rice-Mele model. An appropriate topological invariant for the many-body case is the change of polarization per pump cycle, which we compute for various interaction strengths from infinite-size matrix-product-state simulations. We verify that the charge pumping remains quantized as long as the pump cycle avoids the superfluid phase. In the limit of hardcore bosons, the quantized pumped charge can be understood from single-particle properties such as the integrated Berry curvature constructed from Bloch states, while this picture breaks down at finite interaction strengths. These two properties---robust quantized charge transport in an interacting system of bosons and the breakdown of a single-particle invariant---could both be measured with ultracold quantum gases extending a previous experiment [Lohse et al., Nat. Phys. 12, 350 (2016)]. Furthermore, we investigate the entanglement spectrum of the Rice-Mele model and argue that the quantized charge pumping is encoded in a winding of the spectral flow in the entanglement spectrum over a pump cycle.
Authors: A. Hayward, C. Schweizer, M. Lohse, M. Aidelsburger, F. Heidrich-Meisner
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Awards: G1124226719, G1633018821, G1871477277, Quantensimulatoren: Von photonischen zu atomaren Systemen, G5261598906, FOR 2414: Artificial Gauge Fields and Interacting Topological Phases in Ultracold Atoms, G5603896232, G5711306785, Die deutschfranzösischen Kriege vom Siebenjährigen Krieg bis zum Zweiten Weltkrieg in vergleichender kulturgeschichtlicher Perspektive, Kavli Institute for Theoretical Physics, G985207216
OpenAlex ID: W2897804186