Electronic structure of ${\mathrm{In}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}$ studied by photoemission spectroscopy: Comparison with ${\mathrm{Ga}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}$

We have investigated the electronic structure of the p-type diluted magnetic semiconductor ${\mathrm{In}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}$ by photoemission spectroscopy. The Mn $3d$ partial density of states is found to be basically similar to that of ${\mathrm{Ga}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}.$ However, the impurity-band-like states near the top of the valence band have not been observed by angle-resolved photoemission spectroscopy unlike ${\mathrm{Ga}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}.$ This difference would explain the difference in transport, magnetic and optical properties of ${\mathrm{In}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}$ and ${\mathrm{Ga}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}.$ The different electronic structures are attributed to the weaker Mn $3d-\mathrm{As}4p$ hybridization in ${\mathrm{In}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}$ than in ${\mathrm{Ga}}_{1-x}{\mathrm{Mn}}_x\mathrm{As}.$