Περίληψη:
By using highly sensitive millikelvin superconducting quantum interference device magnetometry, the magnitude of the Curie temperature as a function of the Mn concentration x is determined for thoroughly characterized Ga 1-xMn xN. The interpretation of the results in the frame of tight-binding theory and of Monte Carlo simulations allows us to assign the spin interaction to ferromagnetic superexchange and to point out the limited accuracy of state-of-the-art ab initio methods in predicting the magnetic characteristics of dilute magnetic insulators. © 2012 American Physical Society.
Συγγραφείς:
Sawicki, M.
Devillers, T.
Gałȩski, S.
Simserides, C.
Dobkowska, S.
Faina, B.
Grois, A.
Navarro-Quezada, A.
Trohidou, K.N.
Majewski, J.A.
Dietl, T.
Bonanni, A.