Quantum phase transition induced by Dzyaloshinskii-Moriya interactions in the kagome antiferromagnet

Olivier Cepas (1) , C. M. Fong (2) , P. W. Leung (2) , C. Lhuillier (1)

1 LPTMC - Laboratoire de Physique Théorique de la Matière Condensée
2 HKUST - Hong Kong University of Science and Technology

We argue that the S=1/2 kagome antiferromagnet undergoes a quantum phase transition when the Dzyaloshinskii-Moriya coupling is increased. For DDc the system develops antiferromagnetic long-range order. The quantum critical point is found to be Dc≃0.1J using exact diagonalizations and finite-size scaling. This suggests that the kagome compound ZnCu3(OH)6Cl3 may be in a quantum critical region controlled by this fixed point.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

Olivier Cepas, C. M. Fong, P. W. Leung, C. Lhuillier. Quantum phase transition induced by Dzyaloshinskii-Moriya interactions in the kagome antiferromagnet. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2008, pp.140405. ⟨10.1103/PhysRevB.78.140405⟩. ⟨hal-00705000⟩