کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1658074 1517652 2013 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Simple polymer assisted deposition and strain-induced ferromagnetism of LaCoO3 epitaxial thin films
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Simple polymer assisted deposition and strain-induced ferromagnetism of LaCoO3 epitaxial thin films
چکیده انگلیسی


• LaCoO3 epitaxial thin films were grown by a simple polymer assisted deposition method.
• All the LaCoO3 epitaxial films are found to be ferromagnetic below TC ≈ 85 K.
• Ferromagnetism is enhanced with decreasing thickness of LaCoO3 film.
• There is no relevant report on preparing LCO epitaxial film by the simple PAD method.

LaCoO3 epitaxial films with different thicknesses (~ 20, 50 and 80 nm) were grown on (001) SrTiO3 substrates by a simple polymer assisted deposition method. X-ray diffraction analyses including θ/2θ symmetric scan, ω-scan and in-plane φ-scan indicate that single-phase (001) oriented LaCoO3 films with a pseudotetragonal structure were grown on (001) SrTiO3 substrates successfully, with a biaxial tensile strain from + 2.42% to + 2.60% and tetragonal distortion from 1.47% to 1.63%. Due to the lattice relaxation effect in epitaxial thin film, the biaxial tensile strain is slightly relaxed when the thickness of the LaCoO3 film increases, resulting in an increase of the c-axis constant in contrast to a decrease of the in-plane constants of the film. It is different from LaCoO3 bulk with a nonmagnetic ground state that all the epitaxial films exhibit a ferromagnetic transition at TC ~ 85 K. Combining with the structural and magnetic analyses, it is shown that the strain-induced ferromagnetism in LaCoO3 epitaxial films, corresponding to the higher spin states, origins from the decrease of the energy difference between eg and t2g levels, which is caused by an increase of the unit-cell volume and suppression of the CoO6 octahedral rotations. In addition, the change of FC curve with the thickness of the film reveals that the ferromagnetism is enhanced by the thickness decrease of LaCoO3 film due to the increase of the biaxial tensile strain.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Surface and Coatings Technology - Volume 226, 15 July 2013, Pages 108–112
نویسندگان
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