We have studied the origin of the resistivity peak which is often observed near the Curie temperature on the resistivity temperature characteristic in Ga 1-xMn xAs epitaxial layers. It was confirmed that the Curie temperature of this ferromagnetic semiconductor is strongly dependent on the concentration of free carriers (holes). The concentration of free holes was controlled by an additional nonmagnetic acceptor (Be) at a fixed concentration of magnetic atoms (Mn) of Ga 1-xMn xAs (x = 0.03). We show that the temperature dependences of the resistivity at zero magnetic field and of the magnetoresistance can be successfully described by the magnetoimpurity scattering model proposed by Nagaev [Phys. Rep. 346, 387 (2001)] in both the paramagnetic and the ferromagnetic temperature regions. Quantitative analysis of the experimental data in terms of this model yields the value of the p-d exchange integral J pd = 0.07 eV nm 3 for Ga 0.97Mn 0.03As.
|Journal||Journal of the Korean Physical Society|
|Publication status||Published - 2004 Dec|
- Exchange energy
- Ferromagnetic semiconductors
ASJC Scopus subject areas
- Physics and Astronomy(all)