In this work, the magnetic properties of Ising and XY antiferromagnetic thin-films are investigated each as a function of Neel temperature and thickness for layers （n = 2, 3, 4, 5, 6, and bulk （∞） by means of a me...In this work, the magnetic properties of Ising and XY antiferromagnetic thin-films are investigated each as a function of Neel temperature and thickness for layers （n = 2, 3, 4, 5, 6, and bulk （∞） by means of a mean-field and high temperature series expansion （HTSE） combined with Pade approximant calculations. The scaling law of magnetic susceptibility and magnetization is used to determine the critical exponent γ, veff （mean）, ratio of the critical exponents γ/v, and magnetic properties of Ising and XY antiferromagnetic thin-films for different thickness layers n = 2, 3, 4, 5, 6, and bulk （∞）.展开更多
The crystal structure,magnetic and electrical properties of Bi（0.96）Pb（0.04） FeO3 and Bi（0.92）Pb（0.04）RE（0.04）FeO3（RE=La,Sm,Dy and Yb）polycrystalline samples were prepared by the flash autocombustion techn...The crystal structure,magnetic and electrical properties of Bi（0.96）Pb（0.04） FeO3 and Bi（0.92）Pb（0.04）RE（0.04）FeO3（RE=La,Sm,Dy and Yb）polycrystalline samples were prepared by the flash autocombustion technique.X-ray diffraction（XRD）measurements show that the rare-earth doped compositions crystallized in rhombohedral symmetry of space group R3 c.The undoped sample consisted needle shape particles while rare earth substitution preferred platelet like particles as clarified from high resolution transmission electron microscopy（HRTEM）.Morphological features were examined using field emission scanning electron microscopy（FESEM）.Magnetization measurements showed that Yb^3＋ samples possessed the highest room temperature saturation magnetization while when Bi^3＋ ions were substituted by La^3＋ ions,a smaller MS（0.28 emu/g）was obtained.The coexistence of ferroelectric and magnetic transitions was detected using DSC and χM,indicating the multiferroic characteristics of Bi（0.92）Pb（0.04）RE（0.04）FeO3 crystallites.The Néel temperature shifted upwards with decreasing the ionic radius of rare earth ion.Nice correlation was established between microstructure,morphology and magnetic properties in view of the contribution of magnetocrystalline and shape anisotropy in the magnetic parameters values.展开更多
文摘In this work, the magnetic properties of Ising and XY antiferromagnetic thin-films are investigated each as a function of Neel temperature and thickness for layers （n = 2, 3, 4, 5, 6, and bulk （∞） by means of a mean-field and high temperature series expansion （HTSE） combined with Pade approximant calculations. The scaling law of magnetic susceptibility and magnetization is used to determine the critical exponent γ, veff （mean）, ratio of the critical exponents γ/v, and magnetic properties of Ising and XY antiferromagnetic thin-films for different thickness layers n = 2, 3, 4, 5, 6, and bulk （∞）.
文摘The crystal structure,magnetic and electrical properties of Bi（0.96）Pb（0.04） FeO3 and Bi（0.92）Pb（0.04）RE（0.04）FeO3（RE=La,Sm,Dy and Yb）polycrystalline samples were prepared by the flash autocombustion technique.X-ray diffraction（XRD）measurements show that the rare-earth doped compositions crystallized in rhombohedral symmetry of space group R3 c.The undoped sample consisted needle shape particles while rare earth substitution preferred platelet like particles as clarified from high resolution transmission electron microscopy（HRTEM）.Morphological features were examined using field emission scanning electron microscopy（FESEM）.Magnetization measurements showed that Yb^3＋ samples possessed the highest room temperature saturation magnetization while when Bi^3＋ ions were substituted by La^3＋ ions,a smaller MS（0.28 emu/g）was obtained.The coexistence of ferroelectric and magnetic transitions was detected using DSC and χM,indicating the multiferroic characteristics of Bi（0.92）Pb（0.04）RE（0.04）FeO3 crystallites.The Néel temperature shifted upwards with decreasing the ionic radius of rare earth ion.Nice correlation was established between microstructure,morphology and magnetic properties in view of the contribution of magnetocrystalline and shape anisotropy in the magnetic parameters values.
