AVS 49th International Symposium
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI+EL+SC-TuM

Paper MI+EL+SC-TuM6
Self-compensation in Manganese-doped Ferromagnetic Semiconductors

Tuesday, November 5, 2002, 10:00 am, Room C-205

Session: Ferromagnetic Semiconductors
Presenter: S.C. Erwin, Naval Research Laboratory
Authors: S.C. Erwin, Naval Research Laboratory
A.G. Petukhov, Naval Research Laboratory
Correspondent: Click to Email
We present theoretical evidence that the observed hole compensation in manganese-doped ferromagnetic semiconductors is due to interstitial manganese. We show that under the non-equilibrium conditions used during growth, interstitial Mn is readily formed near the surface by a simple low-energy adsorption pathway. In GaAs, isolated interstitial Mn impurities are electron donors, each compensating two substitutional Mn acceptors under p-type conditions. We show that partial compensation is a prerequisite for ferromagnetic order below the metal-insulator transition, and that the Curie temperature is highest when 1/6 of the Mn is interstitial.