Pressure effect on low-temperature remanence of multidomain magnetite : change in demagnetization temperature
Pressure effect on low-temperature remanence of multidomain magnetite : change in demagnetization temperature
复制标题
压力对多畴磁铁矿低温剩磁的影响：退磁温度的变化
DOI：
10.1029/2011gl050402
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
M.Sato
中科院分区：
文献类型：
--
作者：
石黒静児;Theerasarn Pianpanit;長谷川裕記;M.Sato
我们对磁铁矿的低温剩磁在高达0.7 Gpa的高压下进行了第一次情景热退磁实验，研究了定义为剩磁快速下降的退磁温度(Td)与压力的关系。在专门为MPMS设计的活塞筒式高压室中设置了多磁区磁铁矿颗粒样品。我们对(1)在20K的饱和等温剩磁和(2)在300K到20K的场冷却剩磁进行了零场升温。我们的测量结果表明，在2.9K/Gpa的−压力下，Td明显减小，尽管先前的研究得出了一个正值。结合其他物理性质的相变数据，认为在ZFW过程中120K附近的低温剩磁急剧下降是与Verwey相变有关的物性变化之一。
We have conducted the firstin‐situthermal demagnetization experiments on low‐temperature remanences of magnetite under high pressure up to 0.7 GPa, to investigate the pressure dependence of the demagnetization temperature (Td) defined as rapid decreases in the remanences. A sample of multidomain magnetite particles was set up in the piston‐cylinder‐type high‐pressure cell specially designed for an MPMS. We conducted zero‐field warming (ZFW) on (1) saturation isothermal remanent magnetizations imparted at 20 K and (2) remanences given by field cooling from 300 to 20 K. Our measurements show a clear decrease inTdwith pressure at a rate of −2.9 K/GPa, although a positive rate was inferred by the previous study. Combining with other transition data of physical properties, sharp declines in low‐temperature remanences around 120 K during ZFW are considered as one of the physical property changes associated with the Verwey transition.