Suzuki T, Katsumura M, Taniguchi K, Arima T, Katsufuji T
Department of Physics, Waseda University, Tokyo 169-8555, Japan.
Phys Rev Lett. 2007 Mar 23;98(12):127203. doi: 10.1103/PhysRevLett.98.127203.
We studied the structural properties of an orbital-spin-coupled spinel oxide, MnV2O4, mainly by single-crystal x-ray diffraction measurement. It was found that a structural phase transition from cubic to tetragonal and ferrimagnetic ordering occur at the same temperature (Ts,TN=57 K). The structural phase transition was induced also by magnetic field above Ts. In addition, magnetic-field-induced alignment of tetragonal domains results in large magnetostriction below Ts. We also found that the structural phase transition is caused by the antiferro-type ordering of the V t2g orbitals.
我们主要通过单晶X射线衍射测量研究了一种轨道-自旋耦合尖晶石氧化物MnV2O4的结构特性。发现从立方相到四方相的结构相变以及亚铁磁有序在相同温度（Ts，TN = 57 K）下发生。在Ts以上，磁场也会诱发结构相变。此外，在Ts以下，磁场诱导的四方畴排列会导致大的磁致伸缩。我们还发现结构相变是由V t2g轨道的反铁磁型有序引起的。
