Naslov
Onfluence of oxygen stoichiometry on transport, optical and magnetic properties of the room-temperature ferrimagnetic oxide semiconductor Fe_1.5Ti_0.5O_3-δ

Autori
Ndilimabaka, Herve ; Dumont, Yves ; Popova, E. ; Basletić, Mario ; Desfonds, P. ; Bibes, Manuel ; Godlewski, M. ; Bouzehouane, Karim ; Jomard, F. ; Keller, N

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
52nd Annual Conference on Magnetism and Magnetic Materials (MMM2007)Tampa (SAD) / - , 2007

Skup
52nd Annual Conference on Magnetism and Magnetic Materials (MMM2007) Tampa (SAD)

Mjesto i datum
Tampa (FL), Sjedinjene Američke Države, 05.11.2007. - 09.11.2007

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
spintronic; epitaxial thin films; PLD; magnetic properties

Sažetak
Iron-titanium oxide Fe_1.5Ti_0.5O_3-d obtained by substituting iron by titanium in the hematite structure alpha-Fe_2O_3 is proposed as a "spintronic" material beyond room-temperature: experimental results on bulk and thin films show Fe_2-xTi_xO_3-d to be both magnetic and semiconducting depending on Ti content. Although pure ilmenite FeTiO_3 and pure hematite alpha-Fe_2O_3 are antiferromagnets and insulators, ab-initio calculations predict a half-metallic behaviour for x=0.5. We present here the results obtained for Fe_1.5Ti_0.5O_3-d on epitaxial thin films, grown by pulsed laser deposition technique on c-sapphire at various oxygen pressures (P_O2). The magnetic properties were investigated by SQUID, the electrical properties using classical resistance and Hall effect, and optical absorption using UV-Vis-NIR spectrophotometer. For all oxygen pressures, epitaxial films are single phase. P_O2 appears to be critical parameter for both magnetic and semiconducting properties. High n-type conductivity is obtained at low P_O2 whereas high saturation magnetization M_S and remanence M_R stands for high P_O2 (see fig). Optical absorption data allow associating conduction with the formation of an impurity band.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA