Wihuri Physical Laboratory, Department of Physics and Astronomy, University of Turku, Turku, Finland.
J Phys Condens Matter. 2012 May 30;24(21):216002. doi: 10.1088/0953-8984/24/21/216002. Epub 2012 Apr 27.
The present paper reports detailed structural and magnetic characterization of the low-bandwidth manganite Pr(1-x)Ca(x)MnO(3) (with x = 0.0-0.5) (PCMO) polycrystalline samples. With increasing Ca content, reduction of the unit cell volume and improvement in perovskite structure symmetry was observed at room temperature. Magnetic characterization shows the signature of coexisting AFM-FM ordering and spin-glass phase at the low doping range (x = 0.0-0.2) while increased hole doping (x = 0.3-0.5) leads to charge ordering, training effect and an irreversible metamagnetic phenomenon. The large irreversible metamagnetism in the CO phase of PCMO and the corresponding spin memory effect is a direct consequence of hysteretic first-order phase transition arising from the weakening of the CO state under the external magnetic field and trapping of the spins due to a strong pinning potential in the material.
本文报道了低带宽锰氧化物 Pr(1-x)Ca(x)MnO(3)（其中 x = 0.0-0.5）（PCMO）多晶样品的详细结构和磁性特征。随着 Ca 含量的增加，室温下观察到单位晶胞体积减小和钙钛矿结构对称性提高。磁性特征表明，在低掺杂范围（x = 0.0-0.2）存在共存 AFM-FM 有序和自旋玻璃相，而增加空穴掺杂（x = 0.3-0.5）则导致电荷有序、训练效应和不可逆的顺磁现象。PCMO 的 CO 相中的大不可逆顺磁现象和相应的自旋记忆效应是由于外磁场下 CO 状态的减弱以及材料中强钉扎势导致的自旋捕获导致的滞后一级相变的直接结果。
