Journal of Low Temperature Physics
Triple-Core Structure of the Double-Core Vortex in Superfluid $$^3$$He-B
Riku Rantanen
Abstract
Abstract The order parameter of superfluid $$^3$$ 3 He involves nine complex components, and the multicomponent structure allows quantized vortices in superfluid $$^3$$ 3 He to have complicated cores. One of the vortices found in the B phase is the double-core vortex, which has been often described as a pair of two half-quantum vortices (HQVs) connected by a domain wall. Our numerical calculations of the core structure suggest an alternative representation of the vortex as a combination of three vortices, one in each component of the spin-triplet superfluid. Based on the results we present a qualitative analytical model for the triple-core structure of the double-core vortex. Additionally we numerically calculate the structure of a double-core vortex stretched between pinning sites, and show that the HQV picture becomes more applicable when separation between subcores becomes large.