Abstract:
Based on the results of ab initio electronic structure modeling, the phase separation during magnetic phase transitions of the first kind in ferromagnetic La$_{1-x}$Ca$_x$MnO$_3$ lanthanum manganite is studied. It has been found that the stratification occurs due to a negative mode-mode interaction in the spin system, which is a necessary condition for the first-order phase transition in the Ginzburg–Landau theory. It is shown that due to the peculiarities of the electronic structure during phase separation, metal droplets possess scalar spin chirality. This leads to sd scattering by spin inhomogeneities, which causes the Anderson metal-semiconductor transition near the Curie temperature and the appearance of the chiral Hall effect.
Keywords:first-order phase transition, spin density fluctuations, phase separation, Andersen localization, spin chirality, Hall effect.
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