Phase diagram of a lattice of vortex molecules in multicomponent superconductors and multilayer cuprate superconductors

The Abrikosov lattice in the multilayer cuprate superconductor CuBa 2 Ca 3 Cu 3 O y (Cu-1223) has been experimentally and theoretically demonstrated to be composed of vortex molecules. Cu-1223 is considered to be a typical multicomponent superconductor. We show that in such a system the rotational freedom around the axis of the vortex molecular tube generates orientational disorder and the orientational glass (or crystal) phase, which is never present in conventional vortex lattices consisting of axisymmetric vortices. The emergence of the orientational glass phase and orientational order phase with orthorhombic distortion is a general property of vortex molecule lattices of the multiband type of multicomponent superconductors.