Topological Defects & Vortices

Click to place vortex defects — winding numbers classify them topologically

Create Defects

Total winding: 0 (topologically conserved)
n = (1/2π) ∮ ∇θ · dl
Vortex defects in 2D order parameter fields (XY magnets, superfluid, liquid crystals) are characterized by integer winding numbers.

n=+1: source/vortex — arrows orbit CCW
n=-1: antivortex — arrows orbit CW
n=½: half-vortex in nematics (head-tail symmetry)

Kosterlitz-Thouless transition: vortex–antivortex pairs unbind at T_KT.