Thermodynamic properties of a spin-1/2 spin-liquid state in a κ-type organic salt

Satoshi Yamashita, Yasuhiro Nakazawa, Masaharu Oguni, Yugo Oshima, Hiroyuki Nojiri, Yasuhiro Shimizu, Kazuya Miyagawa, Kazushi Kanoda

Research output: Contribution to journalArticlepeer-review

410 Citations (Scopus)


In two-dimensional triangular lattices, geometric frustration prohibits the formation of ordering even at the lowest temperatures, and therefore a liquid-like ground state is expected. The spin-liquid problem has been one of the central topics of condensed-matter science for more than 30 yr in relation to the resonating-valence-bond model. One of the characteristic features proposed is the existence of a linear temperature-dependent contribution to the heat capacity, as the degeneracy of the energy states should give rise to gapless excitations. Here, we show thermodynamic evidence for the realization of a spin-liquid ground state through a single-crystal calorimetric study of the dimer-based organic charge-transfer salt κ-(BEDT-TTF)2Cu2(CN)3, with a triangular lattice structure down to 75 mK. In addition, we report an unexpected hump structure in the heat capacity around 6 K, which may indicate a crossover into the quantum spin liquid.

Original languageEnglish
Pages (from-to)459-462
Number of pages4
JournalNature Physics
Issue number6
Publication statusPublished - 2008 Jun


Dive into the research topics of 'Thermodynamic properties of a spin-1/2 spin-liquid state in a κ-type organic salt'. Together they form a unique fingerprint.

Cite this