Figure 1

Secondary ion mass spectroscopy (SIMS) depth profiles of deuterated ${\mathrm{Ga}}_{0.963}{\mathrm{Mn}}_{0.037}\mathrm{As}$. Within the experimental uncertainty, D is incorporated into GaMnAs with the same concentration as Mn.Reuse & Permissions

Figure 2

(a) Comparison of the dc magnetization $M(H)$ loops of ${\mathrm{Ga}}_{0.963}{\mathrm{Mn}}_{0.037}\mathrm{As}$ in the as-grown state (full squares) and after deuteration (open circles) at $T=20\mathrm{K}$ with the external magnetic field in the plane of the thin film. The ferromagnetic hysteresis present in the as-grown film vanishes after the deuteration. (b) Magnetization of the deuterated sample at $T=2\mathrm{K}$ and for a much broader range of magnetic fields $H$ (open circles). The data are best described by a Brillouin-type magnetization, with $g=2$ and $J=5/2$ (thick straight line) expected for Mn atoms with a $3d^5$ configuration (Mn in its oxidation state $2+$).Reuse & Permissions

Figure 3

Temperature dependence of the dark conductivity of ${\mathrm{Ga}}_{0.963}{\mathrm{Mn}}_{0.037}\mathrm{As}$ before and after deuteration. The as-grown film exhibits a nearly temperature-independent, metallic conductivity (dash-dotted line). In contrast, deuterated ${\mathrm{Ga}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}$ is semiconducting (full line), the dark conductivity being activated with $E_a\approx (50\pm 20)\mathrm{meV}$ at high temperatures (dashed line). The insets show an electron-counting picture of the Mn acceptor in GaAs, in which the valence electrons are depicted as full circles in the $4s{p}^3$ and $3d$ orbitals. Mn incorporated on a substitutional Ga site acts as an acceptor. An electron from the GaAs valence band is thus required to saturate all bonds, resulting in a delocalized hole not shown. Upon deuteration, all bonds are saturated without the need for valence-band electrons. This explains the drastic reduction of the density of free holes and the configuration of Mn after the deuteration.Reuse & Permissions