Realizing the Harper model with Ultracold Atoms in a Ring Lattice
| Autor: | Jacob Christ, Kunal K. Das |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Physics
Condensed Matter::Quantum Gases Band gap FOS: Physical sciences Perturbation (astronomy) 01 natural sciences Uniform rotation 010305 fluids & plasmas Fractal Quantum Gases (cond-mat.quant-gas) Critical point (thermodynamics) Ultracold atom Quantum mechanics Lattice (order) 0103 physical sciences Edge states 010306 general physics Condensed Matter - Quantum Gases |
| Popis: | We demonstrate that all of the salient features of the Harper-Hofstadter model can be implemented with ultracold atoms trapped in a bichromatic ring-shaped lattice. Using realistic sinusoidal lattice potentials rather than assume the idealized tight-binding picture, we determine the optimal conditions necessary to realize the critical point where the spectrum becomes fractal, and identify the nature and cause of the departures from the discrete model predictions. We also show that even with a commensurate ring with a few lattice sites, the Aubry-Andr\'e localization transition can be realized. Localized states that behave like edge states with energies that reside in the band gaps can be generated by introducing a surprisingly small local perturbation within the ring. Spectrum oscillation arising from complex coupling can be implemented by uniform rotation of the ring, but with certain significant differences that are explained Comment: 8 pages and 8 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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