SU(4) quantum Hall skyrmions in graphene in the quarter-filled N=0 Landau level

Skyrmions are present in multi-component quantum Hall systems where the splittings of Landau sub-levels are small compared to the Coulomb energy. Using a minimal field theory obtained by a variational approach, we study various types of charge-1 skyrmions in the vicinity of the quarter-filled N=0 Landau level of graphene. We find novel texture states in the spin-pseudospin-entanglement channel, as well as the transitions between phases corresponding to different skyrmion types [1]. Our studies provide references for STM/STS imaging of the textured quantum Hall states in graphene and suggest a refined picture for charge transport in the multi-component quantum Hall systems. [1] Lian et al., PRL 117,056806(2016)