Effects of laser floating zone processing on electrical and magnetic properties of (Ca,Pr)MnO3 system

Manganites present fascinating physical properties which can be tuned according with the method and pro-cessing conditions. In this work, Ca1-xPrxMnO3 (x = 0.03, 0.06, 0.1) materials were prepared by the Laser Floating Zone (LFZ) technique, under different pulling rates (25-100 mm/h) in air and argon atmospheres, obtaining fibres with 2.5 mm diameter. Such processing conditions promote the formation of secondary phases in (Ca,Pr)MnO3 fibres. The formation of the perovskite phase at slow pulling rates was observed. The effects of the LFZ conditions on the phase composition, microstructural features, electric and magnetic properties of as-grown and thermally post-processed fibres are analysed and discussed. The results indicate that the LFZ processing conditions have a great impact on the electrical and magnetic properties of the prepared manganites. Secondary phases increase with pulling rate and the effects imposed by their formation can be minimized by additional heat treatment at high temperatures, improving the electric conductivity and magnetization of the thermally-treated fibres.

Automated summary

In this study, Ca1-xPrxMnO3 (x = 0.03, 0.06, 0.1) materials were prepared using the Laser Floating Zone (LFZ) technique under different pulling rates (25-100 mm/h) in air and argon atmospheres. The formation of secondary phases in (Ca,Pr)MnO3 fibers was promoted by the processing conditions, and the perovskite phase was observed at slower pulling rates. The effects of LFZ conditions on the phase composition, microstructural features, electric and magnetic properties of the fibers were analyzed and discussed. The results showed that LFZ processing conditions greatly influenced the electrical and magnetic properties of the prepared manganites. The formation of secondary phases increased with pulling rate, but additional heat treatment at high temperatures minimized their effects and improved the electrical conductivity and magnetization of the thermally-treated fibers.