Evolution of spin wave excitations of Mn3Sn in different magnetic ordered phases

Mn3Sn has very complex magnetic ordered phase, a clear magnetic phase transition happens at T=~280K accompanied by the vanishing of AHE.For our Mn3Sn crystal grown by flux method, by using polarised neutron diffraction, we found a magnetic reflection splitting below that usually known phase transition temperature T=280K indicating the existence of a new incommensurate magnetic ordered phase in Mn3Sn.So we would like to apply 4 days neutron beamtime at time of flight spectrometer Merlin to re-investigate the evolution of spin waves in these different magnetic ordered phases for better understanding of the exchange interactions and the influence of different magnetic ordered phase on this Weyl system.

Mn3Sn具有极为复杂的磁有序相，在T≈280K时发生显著磁相变，且伴随反常霍尔效应（Anomalous Hall Effect，AHE）的消失。针对我们采用助熔剂法生长的Mn3Sn晶体，通过极化中子衍射技术，我们发现其在已知相变温度T=280K以下存在磁反射分裂现象，这表明Mn3Sn中存在一种新的非公度磁有序相。因此，我们申请在飞行时间谱仪Merlin上使用4天的中子束流时间，重新研究这些不同磁有序相中的自旋波演化规律，以更深入理解交换相互作用及不同磁有序相对该外尔系统的影响。