mu SR insight into the impurity problem in quantum kagome antiferromagnets

Article

关键词: LIQUID GROUND-STATE;    SPIN;   

DOI  :  10.1103/PhysRevB.94.024438

来源: SCIE

【 摘 要 】

Impurities, which are unavoidable in real materials, may play an important role in the magnetism of frustrated spin systems with a spin-liquid ground state. We address the impurity issue in quantum kagome antiferromagnets by investigating ZnCu3(OH)(6)SO4 (Zn-brochantite) by means of muon spin spectroscopy. We show that muons dominantly couple to impurities, originating from Cu-Zn intersite disorder, and that the impurity spins are highly correlated with the kagome spins, allowing us to probe the host kagome physics via a Kondo-like effect. The low-temperature plateau in the impurity susceptibility suggests that the kagome spin-liquid ground state is gapless. The corresponding spin fluctuations exhibit an unconventional spectral density and a nontrivial field dependence.

【 授权许可】

Free