Microstructure and magnetic properties of vapor-grown CdTe:Cr crystals with doping-induced precipitates

The effects of heavy doping with Cr and doping-induced precipitation on the magnetism of CdTe crystals, grown from the vapor phase, were investigated by means of different analytical electron microscopy techniques and magnetic measurements. It was revealed that upon post-grown cooling of the crystals, monoclinic [Cr(Cd)](3)Te-4 precipitates with 3.7 at% of Cd nucleate and then form nano-thick single crystalline platelets on the {111} planes of the zinc-blende type Cd(Cr)Te matrix with the orientation relation of (100)([Cr(Cd)]3Te4)//(111)(Cd(Cr)Te) and[011]([Cr(Cd)]3Te4)//[011](Cd(Cr)Te). The ferromagnetism of the CdTe:Cr crystals was confirmed in the range from liquid nitrogen temperature to above room temperatures by magnetization measurements using a vibrating sample magnetometer. Off-axis electron holography experiment proved that the ferromagnetism is mostly governed by [Cr(Cd)](3)Te-4 particles both at liquid nitrogen temperature and at room temperature. It also revealed the anisotropy of the precipitates' magnetic properties. The obtained results indicate the precipitation of magnetic dopants as an effective tool to induce high-temperature ferromagnetism into CdTe bulk crystals, which is of tight relevance for their potential spintronic application. [GRAPHICS] .

Automated summary

The effects of heavy doping with Cr and doping-induced precipitation on the magnetism of CdTe crystals were investigated. It was found that monoclinic [Cr(Cd)]3Te4 precipitates formed on the {111} planes of Cd(Cr)Te matrix. The CdTe:Cr crystals were confirmed to have ferromagnetism from liquid nitrogen temperature to above room temperatures.