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Enhanced ferromagnetism was observed from the H2O2-treated p-type (Zn0.93Mn0.07)O:As layer. Compared with the untreated sample, the H2O2-treated sample showed the enlarged ferromagnetic hysteresis loop with approximately two-times-increased spontaneous magnetization. And also, in comparison with the untreated sample (TC∼280 K), the H2O2-treated sample exhibited to have the increased TC persisting up to above 350 K. These results were confirmed to originate from the enhanced p-d hybridization due to the decrease in negatively charged residual background carriers. This is because the increased effective g-factor resulting from the decrease in oxygen-related defects acting as native deep donors was observed from the H2O2-treated sample. [ABSTRACT FROM AUTHOR]

The As-doped p-type (Zn0.93Mn0.07)O layers show a strong dependence of their ferromagnetic properties on the hole conductivity that were controlled through the modification of negative background-charge density by changing the oxygen partial pressure during the initial growth stage before As doping. Curie temperature and spontaneous magnetization were observed to be increased as the hole conductivity increases. This result was confirmed to originate from stabilizations of incorporated Mn2+ ions and doped As acceptors, which can give rise to long-range ferromagnetic coupling. [ABSTRACT FROM AUTHOR]

Transition related to the Mn–Zn interaction was observed in photoluminescence (PL) study of the InMnP:Zn epilayer and the peak position blueshifted with increasing Mn concentration. X-ray photoelectron spectroscopy was used to clarify the blueshift of the PL peak. The binding energy shifts of Mn 2p and Zn 2p core levels indicative of the interaction between Mn and Zn were observed. This mutual interaction between Mn 2p and Zn 2p agrees with the result that the Mn-related transition in InMnP:Zn codoped with Zn is shifted to the higher energy region in comparison with InMnP without additional doping of Zn. [ABSTRACT FROM AUTHOR]

The As-doped (Zn0.93Mn0.07)O thin film prepared by As+ ion implantation showed a clear peak of (A0,X) having acceptor binding energy of 181 meV. The sample showed high TC ferromagnetism persisting up to 285 K. The contribution of magnetization from Mn ion at 280 K was determined to be 0.13μB/Mn. The improved ferromagnetism is expected to be originated from hole-induced ferromagnetism and enhanced magnetic anisotropy because crystallographically improved sample showed p-type conductivity with hole concentration of 4.8×1018 cm-3 and hole mobility of 11.8 cm2 V-1 s-1. These results suggest that high TC ferromagnetism can be realized by codoping the acceptor dopant and improving the magnetic anisotropy. [ABSTRACT FROM AUTHOR]

InMnP:Zn samples implanted with Mn (10 at. %) were annealed at 350 °C for 60 s and at 450 °C for 30 s. Using transmittance electron microscopy, both single crystalline and polycrystalline structures containing MnP and InMn3 sized ∼20 nm were observed depending on the annealing condition. These samples exhibited two different Curie temperatures: TC1 at 291 K and another well above 291 K. The high temperature-ferromagnetic behavior up to TC1 and above TC2 is believed to have originated from two magnetic MnP and InMn3 phases, respectively. [ABSTRACT FROM AUTHOR]

P-type bulk InP was prepared by the liquid encapsulated Czochralski method and subsequently diffused with Mn by heat treatment after the evaporation of Mn on top of InP:Zn using a molecular beam epitaxy system. The characteristics of Mn-diffused InMnP:Zn were investigated by an energy dispersive x-ray spectroscopy, photoluminescence, and a superconducting quantum interference device magnetometer measurements. The samples were characterized by transmission electron microscopy and no evidence of secondary phase formation of InMnP:Zn was found. The results of energy dispersive x-ray peak displayed injected concentration of Mn near 3%. The results of photoluminescence measurement showed that optical broad transitions related to Mn appeared around 1.2 eV and it was confirmed that the transitions around 1.2 eV were Mn-related band by the diffusion of Mn into InP:Zn. Clear ferromagnetic hysteresis loops were observed at 10 and 300 K and the temperature-dependent magnetization showed ferromagnetic behavior around 300 K, which is caused by carrier-mediated ferromagnetism in InMnP:Zn. It is found that a ferromagnetic semiconductor at room temperature can be formed in diluted magnetic semiconductor based on GaMnN and InMnP additionally co-doped with Mg and Zn, respectively. [ABSTRACT FROM AUTHOR]