Kumar Manoj, Yadav K L
Smart Material Research Laboratory, Department of Physics, Indian Institute of Technology, Roorkee-247667, India.
J Phys Condens Matter. 2007 Jun 20;19(24):242202. doi: 10.1088/0953-8984/19/24/242202. Epub 2007 May 18.
We report magnetoelectric coupling at room temperature between ferroelectric and magnetic order parameters in Mn-doped PbTiO(3) compounds prepared by a solid-state reaction method. X-ray diffraction showed that PbMn(x)Ti(1-x)O(3) (x = 0.1, 0.3 and 0.5) compounds were single phase. The Mn substitution reduced the lattice distortion, i.e., the c/a ratio, and hence the ferroelectric Curie temperature (T(C)) decreased with increasing Mn content. High-temperature magnetization measurements showed that the ferromagnetic Curie temperature (T(M)) decreases with increasing Mn in PbMn(x)Ti(1-x)O(3). An anomaly in the dielectric constant (ε) was observed in the vicinity of the ferromagnetic transition temperature. These samples exhibited magnetism and ferroelectricity simultaneously at room temperature, which was evidenced from the coexistence of saturated magnetization and polarization hysteresis loops. An enhancement in saturation polarization after poling the samples in the magnetic field was evidence of magnetoelectric coupling at room temperature. An enhancement of 11-13% in polarization was observed after poling the samples in a magnetic field at 1.2 T.
我们报道了通过固态反应法制备的 Mn 掺杂 PbTiO₃ 化合物在室温下铁电和磁有序参数之间的磁电耦合。X 射线衍射表明 PbMnₓTi₁₋ₓO₃（x = 0.1、0.3 和 0.5）化合物为单相。Mn 的取代降低了晶格畸变，即 c/a 比，因此铁电居里温度（T(C)）随 Mn 含量的增加而降低。高温磁化测量表明，在 PbMnₓTi₁₋ₓO₃ 中，铁磁居里温度（T(M)）随 Mn 的增加而降低。在铁磁转变温度附近观察到介电常数（ε）出现异常。这些样品在室温下同时表现出磁性和铁电性，这从饱和磁化和极化滞后回线的共存中得到证明。在磁场中对样品进行极化后，饱和极化增强，这是室温下磁电耦合的证据。在 1.2 T 的磁场中对样品进行极化后，观察到极化增强了 11 - 13%。
