Thermal fluctuations and vortex lattice structures in chiral p-wave superconductors: Robustness of double-quanta vortices

We use large-scale Monte-Carlo simulations to study thermal fluctuations in chiral p-wave superconductors in an applied magnetic field in three dimensions. We consider the thermal stability of previously predicted unusual double-quanta flux-line lattice ground states in such superconductors. In previous works it was shown that, neglecting thermal fluctuations, a chiral p-wave superconductor forms a hexagonal lattice of doubly-quantized vortices, except extremely close to the vicinity of Hc2 where double-quanta vortices split apart. We find dissociation of double-quanta vortices driven by thermal fluctuations. However, our calculations also show that the previous predictions of hexagonal doubly-quantized vortices, where thermal fluctuations were ignored, are very robust in the considered model.