CPA density of states and conductivity in a double-exchange system containing impurities

Abstract

We study density of states and conductivity of the doped double-exchange system, treating interaction of charge carriers both with the localized spins and with the impurities in the coherent potential approximation. It is shown that under appropriate conditions there is a gap between the conduction band and the impurity band in paramagnetic phase, while the density of states is gapless in ferromagnetic phase. This can explain metal-insulator transition frequently observed in manganites and magnetic semiconductors. Activated conductivity in the insulator phase is numerically calculated.

5 pages, 2 eps figures, LaTex2e, EPJ macro package (style files included). The calculations done for realistic model predict that a gap appears between the conduction band and the impurity band in paramagnetic phase, while the density of states is gapless in ferromagnetic phase

Cited by in corpus (5)

• Ferromagnetism and electron-phonon coupling in the manganites
• Ferromagnetic transition in a double-exchange system containing impurities
• Ferromagnetic transition in a double-exchange system
• Ferromagnetic transition in a double-exchange system containing impurities in the Dynamical Mean Field Approximation
• Ferromagnetic transition in a double-exchange system with alloy disorder