Signatures of orbital loop currents in the spatially resolved local   density of states
  Polarized neutron scattering measurements have suggested that intra-unit cell antiferromagnetism may be associated with the pseudogap phase. Assuming that loop current order is responsible for the observed magnetism, we calculate some signatures of such circulating currents in the local density of states around a single non-magnetic impurity in a coexistence phase with superconductivity. We find a distinct C4 symmetry breaking near the disorder which is also detectable in the resulting quasi-particle interference patterns. 
W. H. P. Nielsen, W. A. Atkinson, B. M. Andersen
cond-mat.supr-con cond-mat.str-el