How do we get smoothly from the anisotropic A phase with gap nodes to . . .

. . . . the B phase with an isotropic (or nearly isotropic) gap?

We start in the A phase with nodes in the gap and the L-vector for both up and down spins pairs parallel to the nodal line.

We start in the A phase with nodes in the gap and the L-vector for both up and down spins pairs parallel to the nodal line.

The up spin and down spin nodes (and L-vector directions) separate

The up spin and down spin nodes (and L-vector directions) separate

. . . . . and separate further.

The up spin and down spin nodes finally become antiparallel (making the topological charge of the nodes zero) and can then continuously fill to complete the transformation to the B phase.

The up spin and down spin nodes finally become antiparallel (making the topological charge of the nodes zero) and can then continuously fill to complete the transformation to the B phase.

We thus obtain the above complex structure across the interface.

B phase A phase

The quasiparticle motion.