Figure 1: Scattering processes in chiral spin and charge superfluid states in the ‘double-valley’ band.
From: Chiral magnetism and spontaneous spin Hall effect of interacting Bose superfluids
In the chiral spin state ( +−), two condensate atoms of opposite spin at K and −K are scattered to k and −k (or 2K−k and k−2K). In the chiral charge state, atoms of opposite spin at K and K are scattered to k and 2K−k. Here the solid (dashed) arrows denote ↑ (↓), and the red/blue colours differentiate between the two processes, which must be added symmetrically for every k.
