几何阻挫近藤晶格的金属性自旋液体行为

Metallic spin-liquid behavior of the geometrically frustrated Kondo lattice.

作者信息

Nakatsuji S, Machida Y, Maeno Y, Tayama T, Sakakibara T, Duijn J van, Balicas L, Millican J N, Macaluso R T, Chan Julia Y

机构信息

Department of Physics, Kyoto University, Kyoto 606-8502, Japan.

出版信息

Phys Rev Lett. 2006 Mar 3;96(8):087204. doi: 10.1103/PhysRevLett.96.087204.

DOI:10.1103/PhysRevLett.96.087204

PMID:16606220

Abstract

Strongly frustrated magnetism of the metallic pyrochlore oxide Pr2Ir2O7 has been revealed by single crystal study. While Pr 4f moments have an antiferromagnetic RKKY interaction energy scale of /T*/ = 20 K mediated by Ir 5d-conduction electrons, no magnetic long-range order is found except for partial spin freezing at 120 mK. Instead, the Kondo effect, including a lnT dependence in the resistivity, emerges and leads to a partial screening of the moments below /T*/. Our results indicate that the underscreened moments show spin-liquid behavior below a renormalized correlation scale of 1.7 K.

摘要

单晶研究揭示了金属焦绿石氧化物Pr2Ir2O7的强阻挫磁性。虽然Pr 4f磁矩通过Ir 5d传导电子介导具有/T*/ = 20 K的反铁磁RKKY相互作用能标，但除了在120 mK时部分自旋冻结外，未发现磁长程序。相反，出现了包括电阻率中lnT依赖性的近藤效应，并导致在/T*/以下对磁矩进行部分屏蔽。我们的结果表明，欠屏蔽磁矩在1.7 K的重整化关联尺度以下表现出自旋液体行为。