Improved properties of epitaxial YNixMn1−xO3 films by annealing under high magnetic fields

Abstract

The effect of annealing under a magnetic field on the microstructure and properties of YNi x Mn 1-x O 3 (x=0.33 and 0.5) films has been investigated. It is found that the ferromagnetic transition temperature is significantly enhanced after post annealing in the presence of an 8 T magnetic field. Characterization study shows that the microstructure is affected, obtaining larger grains of uniform size when films are annealed under a magnetic field. The improvement in the ordering temperature of all films is interpreted in terms of the grain growth caused by the magnetic-field driving force for boundary motion where the exchange coupling is high.

Control of composition and structure of ferroelectric oxide thin films grown by pulsed laser deposition

“…Indeed it was shown for example that the cations composition of high temperature superconducting oxides was achieved in thin films from stoichiometric targets whereas the oxygen content was controlled by the deposition and cooling atmosphere [14,15]. Similar results were achieved in other cases like rareearth manganites [16,17]. In contrast, for oxides containing highly volatile cations, like Bi in SBN and K in KTN, an accurate optimization of the deposition conditions is necessary in order to control the thin films composition.…”

Magnetization reversal in bulk and thin films of the ferrimagnetic ErCo0.50Mn0.50O3 perovskite

“…A 248 nm KrF pulsed with 5 Hz repetition rate and 2 J/cm 2 energy density was used. A detailed description of deposition is given elsewhere [8]. Substrate temperature of 740 1C and oxygen pressure of 0.3 and 0.6 mbar were used during deposition.…”

“…These modifications may result in a compromise between magnetism and ferroelectricity and lead to applications in the field of multiferroism. In this sense, epitaxial growth and ex-situ annealing are important to enhance the magnetic and conducting properties thanks to grain growth and improved crystallinity [8] pulsed-laser ablation. Main features are compared with those of bulk ceramics.…”

Application of high magnetic fields in advanced materials processing

“…Whisker alignment seems to be an attractive way to improve the properties of whisker reinforced materials. More recently, Ma et al [39] reported that the ferromagnetic transition temperature was significantly enhanced when YNi x Mn 1−x O 3 films were annealed in the presence of an 8 T magnetic field. Characterization study shows that the microstructure is affected, obtaining larger grains of uniform size.…”