Microscopic study of slablike and rodlike nuclei: Quantum molecular dynamics approach

The structure of cold dense matter at subnuclear densities is investigated by quantum molecular dynamics simulations. We succeeded in showing that the phases with slablike and rodlike nuclei, etc., can be formed dynamically from hot uniform nuclear matter without any assumptions on nuclear shape. We also observe intermediate phases, which have complicated nuclear shapes. Geometrical structures of matter are analyzed with Minkowski functionals, and it is found that intermediate phases can be characterized as those with negative Euler characteristic. Our result suggests the existence of these kinds of phases in addition to the simple "pasta" phases in neutron star crusts.