Department of Materials Science and Metallurgy, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3QZ, United Kingdom.
Phys Rev Lett. 2010 Jun 18;104(24):247202. doi: 10.1103/PhysRevLett.104.247202. Epub 2010 Jun 14.
Using high resolution neutron diffraction and capacitance dilatometry we show that the thermal evolution of the helimagnetic state in CoMnSi is accompanied by a change in interatomic distances of up to 2%, the largest ever found in a metallic magnet. Our results and the picture of competing exchange and strongly anisotropic thermal expansion that we use to understand them sheds light on a new mechanism for large magnetoelastic effects that does not require large spin-orbit coupling.
利用高分辨率中子衍射和电容膨胀法，我们发现 CoMnSi 中螺旋磁态的热演化伴随着原子间距离的变化，可达 2%，这是在金属磁体中发现的最大变化。我们的结果和竞争交换以及强烈各向异性热膨胀的图像表明，存在一种新的大磁弹效应机制，它不需要大的自旋轨道耦合。
