Quantum spin-liquid behavior in the spin-1/2 random-bond Heisenberg antiferromagnet on the kagome lattice

TL;DR

This paper investigates how quenched bond randomness affects the ground state of the spin-1/2 kagome lattice Heisenberg antiferromagnet, revealing a transition to a gapless spin-liquid state relevant to real materials.

Contribution

It demonstrates that sufficient bond randomness induces a transition to a gapless spin-liquid state in the kagome antiferromagnet, providing insights into experimental observations.

Findings

Transition to gapless spin-liquid state with increased randomness

Critical randomness value triggers the phase transition

Implications for understanding herbertsmithite behavior

Abstract

The effect of the quenched bond-randomness on the ordering of the $S=1/2$ antiferromagnetic Heisenberg model on the kagome lattice is investigated by means of an exact-diagonalization method. When the randomness exceeds a critical value, the ground state of the model exhibits a transition within the non-magnetic state into the randomness-relevant gapless spin-liquid state. Implications to the S=1/2 kagome-lattice antiferromagnet herbertsmithite is discussed.