Yaouanc A, de Réotier P Dalmas, Glazkov V, Marin C, Bonville P, Hodges J A, Gubbens P C M, Sakarya S, Baines C
CEA/DSM/Département de Recherche Fondamentale sur la Matière Condensée, Grenoble, France.
Phys Rev Lett. 2005 Jul 22;95(4):047203. doi: 10.1103/PhysRevLett.95.047203.
Using muon-spin-relaxation measurements we show that the pyrochlore compound Gd(2)Ti(2)O(7), in its magnetically ordered phase below approximately 1 K, displays persistent spin dynamics down to temperatures as low as 20 mK. The characteristics of the induced muon relaxation can be accounted for by a scattering process involving two magnetic excitations, with a density of states characterized by an upturn at low energy and a small gap depending linearly on the temperature. We propose that such a density of states is a generic feature of geometrically frustrated magnetic materials.
通过μ子自旋弛豫测量，我们发现烧绿石化合物Gd₂Ti₂O₇在低于约1 K的磁有序相中，在低至20 mK的温度下仍表现出持续的自旋动力学。诱导μ子弛豫的特性可以通过一个涉及两个磁激发的散射过程来解释，其态密度在低能量处有一个上升趋势，并且有一个随温度线性变化的小能隙。我们提出，这样的态密度是几何受挫磁性材料的一个普遍特征。
