Dynamic fingerprint of fractionalized excitations in single-crystalline Cu3Zn(OH)6FBr [post]

Ying Fu, Miao-Ling Lin, Le Wang, Qiye Liu, Lianglong Huang, Wenrui Jiang, Zhanyan Hao, Cai Liu, Hu Zhang, Xingqiang Shi, Jun Zhang, Junfeng Dai (+5 others)
2021 unpublished
Beyond the absence of long-range magnetic orders, the most prominent feature of the elusive quantum spin liquid (QSL) state is the existence of fractionalized spin excitations, i.e., spinons. When the system orders, the spin-wave excitation appears as the bound state of the spinon-antispinon pair. Although scarcely reported, a direct comparison between similar compounds illustrates the evolution from spinon to magnon. Here, we perform the Raman scattering on single crystals of two quantum
more » ... f two quantum kagome antiferromagnets, of which one is the kagome QSL candidate Cu3Zn(OH)6FBr, and another is an antiferromagnetically ordered compound EuCu3(OH)6Cl3. In Cu3Zn(OH)6FBr, we identify a unique one spinon-antispinon pair component in the E2g magnetic Raman continuum, providing strong evidence for deconfined spinon excitations. In contrast, a sharp magnon peak emerges from the one-pair spinon continuum in the Eg magnetic Raman response once EuCu3(OH)6Cl3 undergoes the antiferromagnetic order transition. From the comparative Raman studies, we can regard the magnon mode as the spinon-antispinon bound state, and the spinon confinement drives the magnetic ordering.
doi:10.21203/rs.3.rs-98671/v1 fatcat:udqdppgegbar5bopuvb5szms3y