Figure 1:

Topological singularities in the phase bands of a periodically driven Hofstadter model at fixed flux 1/3. kx=0, θx=π/3. The panel on the right shows the locations of the zone edge singularity with monopole charge +1 (empty circle) or –1 (solid dot) for t=T1+2π/3Jy.

© De Gruyter