Systematic charge doping and physical property studies for metallic quantum two-dimensional triangular lattice antiferromagnets

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K05515
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: University of Fukui
• Principal Investigator: Kikuchi Hikomitsu 福井大学, 学術研究院工学系部門, 教授 (50234191)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 反強磁性体 / 電気伝導体 / スピンフラストレーション

Outline of Final Research Achievements

The ground state of the two-dimensional triangular lattice magnets is highly degenerate because of the spin frustration effect. New physical properties such as superconductivity is expected to be emerge in the frustrated magnets. In this study, S = 1/2 two-dimensional triangular lattice antiferromagnets Ag2NiO2, AgNiO2 and related compounds showing metallic electrical conductivity are synthesized by a simple and low cost hydrothermal synthesis method. Element substituted materials such as (Ag, Hg) 2NiO2 and Ag2Ni (O, F) 2 are systematically prepared to control the charge properties. We measured magnetic properties and electrical conductivity of the element substituted materials to investigate the effect of the spin frustration on physical properties.

Free Research Field

磁性

Academic Significance and Societal Importance of the Research Achievements

本研究の特色は、金属的伝導性を示す二次元量子フラストレート磁性体を簡単な合成法で作成し、伝導性、磁性に対するドーピングの影響を系統的に調べる点である。従来用いられてきた高圧合成と比較して、合成条件をそろえた試料が容易かつ低コストで作成できる点も特徴である。これらの化合物に対して、積極的に電荷ドーピングを行って物性変化を調べた例はほとんどない。超伝導が発現した場合には、非従来型の超伝導機構による超伝導による可能性が大きく、学問的な意義は大変大きい。