Ding Yang, Haskel Daniel, Tseng Yuan-Chieh, Kaneshita Eiji, van Veenendaal Michel, Mitchell J F, Sinogeikin Stanislav V, Prakapenka Vitali, Mao Ho-kwang
HPSynC, Carnegie Institution of Washington, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2009 Jun 12;102(23):237201. doi: 10.1103/PhysRevLett.102.237201. Epub 2009 Jun 10.
Low temperature Mn K-edge x-ray magnetic circular dichroism and x-ray diffraction measurements were carried out to investigate the stability of the ferromagnetic ground state in manganite La0.75Ca0.25MnO3 under nearly uniform compression using diamond anvil cells. The magnetic dichroism signal gradually decreases with pressure and disappears at 23 GPa, and meanwhile a uniaxial compression of MnO6 octahedra along the b axis is observed to continuously increase with pressure and become anomalously large at 23.5 GPa. These changes are attributed to a ferromagnetic-antiferromagnetic transition that is associated with orbital ordering at high pressure.
利用金刚石对顶砧池进行了低温锰K边X射线磁圆二色性和X射线衍射测量，以研究在近乎均匀压缩条件下，锰酸盐La0.75Ca0.25MnO3中铁磁基态的稳定性。磁二色性信号随压力逐渐降低，并在23吉帕时消失，与此同时，观察到MnO6八面体沿b轴的单轴压缩随压力持续增加，并在23.5吉帕时变得异常大。这些变化归因于与高压下轨道有序化相关的铁磁-反铁磁转变。
