Experimental measurement of the Berry curvature from anomalous transport
Authors: Wimmer M., Price HM., Carusotto I., Peschel U.
Autors Affiliation: Erlangen Grad Sch Adv Opt Technol SAOT, D-91058 Erlangen, Germany; Friedrich Schiller Univ Jena, Inst Solid State Theory & Opt, Abbe Ctr Photon, Max Wien Pl 1, D-07743 Jena, Germany; Univ Trento, INO CNR BEC Ctr, Via Sommarive 14, I-38123 Povo, Italy; Univ Trento, Dept Phys, Via Sommarive 14, I-38123 Povo, Italy
Abstract: The geometric properties of energy bands underlie fascinating phenomena in many systems, including solid-state, ultracold gases and photonics. The local geometric characteristics such as the Berry curvature(1) can be related to global topological invariants such as those classifying the quantum Hall states or topological insulators. Regardless of the band topology, however, any non-zero Berry curvature can have important consequences, such as in the semi-classical evolution of a coherent wavepacket. Here, we experimentally demonstrate that the wavepacket dynamics can be used to directly map out the Berry curvature. To this end, we use optical pulses in two coupled fibre loops to study the discrete time evolution of a wavepacket in a one-dimensional geometric ‘charge’ pump, where the Berry curvature leads to an anomalous displacement of the wavepacket. This is both the first direct observation of Berry curvature effects in an optical system, and a proof-of-principle demonstration that wavepacket dynamics can serve as a high-resolution tool for mapping out geometric properties.
Journal/Review: NATURE PHYSICS
Volume: 13 (6) Pages from: 545 to: 550
KeyWords: EDGE STATES; ULTRACOLD FERMIONS; BLOCH BAND; PHASE; PHOTONICS; TOPOLOGYDOI: 10.1038/NPHYS4050Citations: 73data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-10-24References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here