Quantum spin liquid in frustrated one-dimensional LiCuSbO 4

Abstract

A quantum magnet, LiCuSbO 4, with chains of edge-sharing spin-12 CuO 6 octahedra is reported. While short-range order is observed for T<10K, no zero-field phase transition or spin freezing occurs down to 100mK. Specific heat indicates a distinct high-field phase near the 12T saturation field. Neutron scattering shows incommensurate spin correlations with q=(0.47±0.01)π/a and places an upper limit of 70μeV on any spin gap. Exact diagonalization of 16-spin easy-plane spin-12 chains with competing ferro- and antiferromagnetic interactions (J 1=-75K, J 2=34K) accounts for the T>2K data. © 2012 American Physical Society.