Possible Tomonaga-Luttinger spin liquid state in the spin-1/2 inequilateral diamond-chain compound K3Cu3AlO2(SO4)4

Masayoshi Fujihala; Hiroko Koorikawa; Setsuo Mitsuda; Katsuhiro Morita; Takami Tohyama; Keisuke Tomiyasu; Akihiro Koda; Hirotaka Okabe; Shinichi Itoh; Tetsuya Yokoo; Soshi Ibuka; Makoto Tadokoro; Masaki Itoh; Hajime Sagayama; Reiji Kumai; Youichi Murakami

doi:10.1038/s41598-017-16935-9

Possible Tomonaga-Luttinger spin liquid state in the spin-1/2 inequilateral diamond-chain compound K₃Cu₃AlO₂(SO₄)₄

Sci Rep. 2017 Dec 1;7(1):16785. doi: 10.1038/s41598-017-16935-9.

Authors

Affiliations

¹ Tokyo University of Science, Department of Physics, Tokyo, 162-8601, Japan. fujihara@nsmsmac4.ph.kagu.tus.ac.jp.
² Tokyo University of Science, Department of Physics, Tokyo, 162-8601, Japan.
³ Tokyo University of Science, Department of Applied Physics, Tokyo, 125-8585, Japan.
⁴ Tohoku University, Department of Physics, Sendai, 980-8578, Japan.
⁵ High Energy Accelerator Research Organization, Muon Science Laboratory and Condensed Matter Research Center, Institute of Materials Structure Science, Tsukuba, 305-0801, Japan.
⁶ High Energy Accelerator Research Organization, Neutron Science Division, Institute of Materials Structure Science, Tsukuba, 305-0801, Japan.
⁷ Tokyo University of Science, Department of Chemistry, Tokyo, 162-8601, Japan.
⁸ High Energy Accelerator Research Organization, Photon Factory, Institute of Materials Structure Science, Tsukuba, 305-0801, Japan.

Abstract

K₃Cu₃AlO₂(SO₄)₄ is a highly one-dimensional spin-1/2 inequilateral diamond-chain antiferromagnet. Spinon continuum and spin-singlet dimer excitations are observed in the inelastic neutron scattering spectra, which is in excellent agreement with a theoretical prediction: a dimer-monomer composite structure, where the dimer is caused by strong antiferromagnetic (AFM) coupling and the monomer forms an almost isolated quantum AFM chain controlling low-energy excitations. Moreover, muon spin rotation/relaxation spectroscopy shows no long-range ordering down to 90 mK, which is roughly three orders of magnitude lower than the exchange interaction of the quantum AFM chain. K₃Cu₃AlO₂(SO₄)₄ is, thus, regarded as a compound that exhibits a Tomonaga-Luttinger spin liquid behavior at low temperatures close to the ground state.

Publication types

Research Support, Non-U.S. Gov't