Structural and magnetic properties are investigated for Fe1-xMnxV2O4 （0≤ x ≤ 1） spinels. As orbital-active Fe^2＋ is substituted with Mn^2＋, the cubie-to-tetragonM transition TsI and the tetragonal-to-orthorhombi...Structural and magnetic properties are investigated for Fe1-xMnxV2O4 （0≤ x ≤ 1） spinels. As orbital-active Fe^2＋ is substituted with Mn^2＋, the cubie-to-tetragonM transition TsI and the tetragonal-to-orthorhombic transition Ts2 gradually decrease. These structural transitions originate from the Fe^2＋ ferro-orbital order （F-OO）. Below Yafet-Kittel （YK） magnetic transition TN2, V^3＋ orbital order （V-OO） plays an important role on global structure. Here x = 0.6 is a critical point. Fe^2＋ F-OO and V^3＋ F-OO coexist for 0 ≤ x ≤ 0.5. For x≥ 0.6, the orbital pattern of V^3＋ is antiferro （AF）-00, and Fe^2＋ F-OO disappears. Structural transition Ts3, accompanied by YK magnetic transition TN2, decreases initially, and then increases at x = 0.6. A scenario for the complex phase diagram arising from the cooperation or competition of Fe^2＋ and V^3＋ orbitals is proposed.展开更多
Ferroelectric and magnetic properties of Fe1-xMnxV2O4 （0 ≤ x ≤ 0.5） spinels are investigated on the basis of dielectric, polarization, and susceptibility measurements. Ferroeleetric polarization is discovered in c...Ferroelectric and magnetic properties of Fe1-xMnxV2O4 （0 ≤ x ≤ 0.5） spinels are investigated on the basis of dielectric, polarization, and susceptibility measurements. Ferroeleetric polarization is discovered in collinear ferrimagnetic and Yafet-Kittel magnetic phases for 0.1 ≤ x ≤ 0.4, which can be tuned by a magnetic field. As orbital-active FJ＋ is substituted with Mn2＋, ferroeleetric polarization decreases for 0 ≤ x ≤ 0.4 and disappears for x=0.5. We propose that the two polar components in ferroelectric polarization originate from the exchange striction mechanism and the spin-current model, respectively.展开更多
基金Supported by the National Basic Research Program of China under Grant Nos 2011CB921904 and 2012CB927402the National Natural Science Foundation of China under Grant Nos 11074142 and 11021464+1 种基金the Key Project of Chinese Ministry of Education under Grant No 309003the Tsinghua TNList Cross-discipline Foundation
文摘Structural and magnetic properties are investigated for Fe1-xMnxV2O4 （0≤ x ≤ 1） spinels. As orbital-active Fe^2＋ is substituted with Mn^2＋, the cubie-to-tetragonM transition TsI and the tetragonal-to-orthorhombic transition Ts2 gradually decrease. These structural transitions originate from the Fe^2＋ ferro-orbital order （F-OO）. Below Yafet-Kittel （YK） magnetic transition TN2, V^3＋ orbital order （V-OO） plays an important role on global structure. Here x = 0.6 is a critical point. Fe^2＋ F-OO and V^3＋ F-OO coexist for 0 ≤ x ≤ 0.5. For x≥ 0.6, the orbital pattern of V^3＋ is antiferro （AF）-00, and Fe^2＋ F-OO disappears. Structural transition Ts3, accompanied by YK magnetic transition TN2, decreases initially, and then increases at x = 0.6. A scenario for the complex phase diagram arising from the cooperation or competition of Fe^2＋ and V^3＋ orbitals is proposed.
基金Supported by the National Basic Research Program of China under Grant Nos 2011CB921904 and 2012CB927402the National Natural Science Foundation of China under Grant Nos 11074142 and 11021464+1 种基金the Key Project of the Ministry of Education of China under Grant No 309003the Tsinghua TNList Cross-discipline Foundation
文摘Ferroelectric and magnetic properties of Fe1-xMnxV2O4 （0 ≤ x ≤ 0.5） spinels are investigated on the basis of dielectric, polarization, and susceptibility measurements. Ferroeleetric polarization is discovered in collinear ferrimagnetic and Yafet-Kittel magnetic phases for 0.1 ≤ x ≤ 0.4, which can be tuned by a magnetic field. As orbital-active FJ＋ is substituted with Mn2＋, ferroeleetric polarization decreases for 0 ≤ x ≤ 0.4 and disappears for x=0.5. We propose that the two polar components in ferroelectric polarization originate from the exchange striction mechanism and the spin-current model, respectively.
