Probing short-range magnetic order in a geometrically frustrated magnet by means of the spin Seebeck effect

作     者：Changjiang Liu Stephen M. Wu John E. Pearson J. Samuel Jiang N. d'Ambrumenil Anand Bhattacharya 

作者机构：Materials Science Division Argonne National Laboratory Lemont Illinois 60439 USA Department of Electrical and Computer Engineering University of Rochester Rochester New York 14627 USA Department of Physics University of Warwick Coventry CV4 7AL United Kingdom 

出 版 物：《Physical Review B》 (Phys. Rev. B)

年 卷 期：2018年第98卷第6期

页      面：060415(R)-060415(R)页

核心收录：

基　　金：US Department of Energy Office of Science, SC Basic Energy Sciences, BES, (DE-AC02-06CH11357) Division of Materials Sciences and Engineering, DMSE 

主　　题：Ferrimagnetism Frustrated magnetism Magnetic order Magnons Spin Seebeck effect Ferrimagnets Kagome lattice Magnetic insulators 

摘      要：The spin Seebeck effect (SSE) is a phenomenon where a spin current is generated from thermal excitations in magnetic materials. It is believed that magnetic long-range order (LRO) is not required for SSE, while short-ranged order (SRO) plays an important role. However, a definitive experimental demonstration of the connection between the SSE and SRO has been missing. Here, we show that the SSE is able to probe a specific SRO in a model geometrically frustrated magnet Gd3Ga5O12 (GGG). A field-induced SRO in GGG is detected by the SSE in the temperature range 2–5 K. The origin of the SRO is verified by comparing the SSE data directly to existing neutron scattering measurements at much lower temperatures (T0.9 K), where field-induced LRO exists. Our theoretical calculations of the magnetic structure further confirm the anisotropic field dependence of the SRO in GGG. These findings establish that the SSE can serve as an effective probe of SRO in geometrically frustrated magnets.