标题： Bi0.5Ca0.5MnO3 中由超高磁场引起的渐进电荷有序熔化 显示英文标题

标题： Gradual charge order melting in Bi0.5Ca0.5MnO3 induced by ultrahigh magnetic field

摘要： 我们通过磁化测量研究了Bi0.5Ca0.5MnO3在超高压磁场下的磁性质。这种化合物表现出巨磁转变，这表明在室温T = 293 K时磁场所诱导的电荷有序熔化。我们发现临界场的温度依赖性，其中最高临界场高于100 T。在低温下，发现巨磁转变在场上升过程中低于70 K时变宽并消失。另一方面，在场下降过程中，即使低于70 K也观察到明显的巨磁转变。这种不寻常的行为可以理解为磁场逐渐熔化电荷有序及其同时重形成。多重序参量的共存可以解释所观察到的一阶相变特征动力学。最后，我们构建了具有超高压磁场下异常临界特性的B-T相图。 显示英文摘要

摘要： We have investigated the magnetic properties of Bi0.5Ca0.5MnO3 under ultrahigh magnetic fields by magnetization measurements. This compound shows the metamagnetic transition which indicates the magnetic field induced charge order melting at the room temperature T = 293 K. We reveled that the temperature dependence of the critical field, where the highest critical field is higher than 100 T. At low temperatures, it has been found that the metamagnetic transitions become broad and vanish in the field ascending process below 70 K. On the other hand, in the field descending process, a clear metamagnetic transition is observed even below 70 K. This unusual behavior can be understood as the gradual charge order melting by magnetic field, and its simultaneous reformation. A coexistence of multiple order parameters can account for the observed characteristic dynamics of the first order phase transition. Finally, we constructed the B-T phase diagram with the unusual critical feature at ultrahigh magnetic fields.