Uncharged compactlike and fractional Lorentz-violating BPS vortices in   the CPT-even sector of the standard model extension
  We have investigated and verified the existence of stable uncharged Bogomol'nyi-Prasad-Sommerfeld (BPS) vortices in the framework of an Abelian Maxwell-Higgs model supplemented with CPT-even and Lorentz-violating (LV) terms belonging to the gauge and Higgs sectors of the standard model extension. The analysis is performed in two situations: first, one by considering the Lorentz violation only in the gauge sector and then in both gauge and Higgs sectors. In the first case, it is observed that the model supports vortices somehow equivalent to the ones appearing in a dielectric medium. The Lorentz violation controls the radial extension (core of the solution) and the magnetic field amplitude of the Abrikosov-Nielsen-Olesen vortices, yielding compactlike defects in an alternative and simpler way than that of $k-$field models. At the end, we consider the Lorentz-violating terms in the gauge and Higgs sectors. It is shown that the full model also supports compactlike uncharged BPS vortices in a modified vacuum, but this time there are two LV parameters controlling the defect structure. Moreover, an interesting novelty is introduced by the LV-Higgs sector: fractional vortex solutions. 
C. Miller, R. Casana, M. M. Ferreira Jr, E. da Hora
hep-th cond-mat.soft cond-mat.supr-con quant-ph