Hole density of ferromagnetic semiconductor (Ga, Mn)As studied via pulsed high magnetic field

Transport measurements of as-grown and annealed (Ga,Mn)As samples were conducted under pulsed high magnetic field up to 40T. Assuming that the magnetization follows modified Brillouin function, we obtained the hole densities of the (Ga,Mn)As samples at various temperatures, which generally increase with temperature and become two times larger after annealing process. The hole density determined by electrical transport measurement at low magnetic field up to 1.5T is found to be underestimated.