title: Polarization of valence band holes in the (Ga,Mn)as diluted magnetic semiconductor.
abstract: We report on direct measurements of the impurity band hole polarization in the diluted magnetic semiconductor (Ga,Mn)As. The polarization of impurity band holes in a magnetic field is strongly enhanced by antiferromagnetic exchange interaction with Mn ions. The temperature dependence of the hole polarization shows a strong increase of this polarization below the Curie temperature. We show that the ground state of the impurity band is formed by uniaxial stress split F=+/-1 states of antiferromagnetically coupled Mn ions (S=5/2) and valence band holes (J=3/2). The gap between the Mn acceptor related impurity band and the valence band is directly measured in a wide range of Mn content.
authors.affiliation: Paul-Drude-Institut für Festkörperelektronik, Berlin, Germany. sapega@dnm.ioffe.rssi.ru
authors.forename: V F
authors.initials: VF
authors.lastname: Sapega
authors.forename: M
authors.initials: M
authors.lastname: Moreno
authors.forename: M
authors.initials: M
authors.lastname: Ramsteiner
authors.forename: L
authors.initials: L
authors.lastname: Däweritz
authors.forename: K H
authors.initials: KH
authors.lastname: Ploog