We have investigated the chemical distributions and the local electronic structure of potential diluted magnetic semiconductor ${\mathrm{Ge}}_{0.94}{\mathrm{Mn}}_{0.06}$ single crystals using scanning photoelectron microscopy (SPEM), x-ray absorption spectroscopy (XAS), and photoemission spectroscopy (PES). The SPEM image shows the stripe-shaped microstructures, which arise from the chemical phase separation between the Mn-rich and Mn-depleted phases. The Mn $2p$ XAS shows that the Mn ions in the Mn-rich region are in the divalent high-spin ${\mathrm{Mn}}^{2+}$ states but that they do not form metallic Mn clusters. The Mn $3d$ PES spectrum exhibits a peak centered at $\sim 4\mathrm{eV}$ below $E_{\mathrm{F}}$ and the negligible spectral weight near $E_{\mathrm{F}}$. This study suggests that the observed ferromagnetism in ${\mathrm{Ge}}_{1-x}{\mathrm{Mn}}_x$ arises from the phase-separated Mn-rich phase.

• Received 2 September 2004

DOI:https://doi.org/10.1103/PhysRevLett.94.147202