Interiors of neutron stars are ultra-dense and may contain a core of deconfined quark matter .
Such a core connects to the outer layers either smoothly or through a sharp microscopic interface or through an intermediate macroscopic layer of inhomogeneous mixed phases , which is globally neutral but locally contains electrically charged domains .
Here I employ a nucleon-meson model under neutron star conditions that shows a first-order chiral phase transition at large densities .
In the vicinity of this chiral transition I calculate the free energies of various mixed phases – different ’ pasta structures ’ – in the Wigner-Seitz approximation .
Crucially , chirally broken nuclear matter and the approximately chirally symmetric phase ( loosely interpreted as quark matter ) are treated on the same footing .
This allows me to compute the interface profiles of bubbles , rods , and slabs fully consistently , taking into account electromagnetic screening effects and without needing the surface tension as an input .
I find that the full numerical results tend to disfavor mixed phases compared to a simple step-like approximation used frequently in the literature and that the predominantly favored pasta structure consists of slabs with a surface tension \Sigma \simeq 6 { MeV } / { fm } ^ { 2 } .