Isovalent Doping Strategy for Manganese Introduction into III-V Diluted Magnetic Semiconductor Nanoparticles: InP:Mn

Abstract

III−V based diluted magnetic semiconductor (DMS) nanoparticles of In(1-x)MnxP (x ≤ 0.0135) have been prepared by slow heating of the reagents in trioctylphosphine oxide (TOPO) or by high-temperature injection of reagents dissolved in trioctylphosphine (TOP) into hot TOPO. The materials were prepared using either Mn(II) or Mn(III) salts as dopants and the resulting nanoparticles have diameters ranging from 2.95 ± 0.39 to 4.77 ± 0.73 nm, as determined from transmission electron micrographs. Chemical analysis of surface-exchanged samples revealed the incorporation of Mn into the crystal lattice with up to 6 Mn atoms per 3.4-nm diameter particle, or the equivalence of ∼1020 Mn atoms/cm3 in a zinc blende bulk lattice. The InP:Mn nanoparticles exhibited a red shift in the room-temperature photoluminescence of 0.02−0.03 eV relative to that for pure InP nanoparticles. Electron paramagnetic resonance studies suggest that the Mn atoms mostly reside near the surface and are Mn2+, regardless of the oxidation state of...