First-principles calculations of exchange interactions in CuAlO_2 based dilute magnetic semiconductors with carrier doping

摘要

The electronic structure and the magnetic properties of carrier doped CuAlO_2 based dilute magnetic semiconductors (DMSs) are calculated by using the Korringa-Kohn-Rostoker method combined with the coherent potential approximation within the local density approximation. Carrier doping treatment is simulated by substitutional Mg at Al site. Curie temperature is estimated by the mean-field approximation from the total energy difference between ferromagnetic states and paramagnetic states. It is found that (Cu_(0.95), V_(0.05))(Al_(1-x), Mg_x)O_2 shows ferromagnetism due to the introduction of holes into paramagnetic (Cu_(0.95), V_(0.05))AlO_2.