2013/01/11 by Hao Zhang, C. A. Lamas
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.87.024415
published as Phys. Rev. B 87, 024415 (2013) · 11 pages, 9 figures, to appear in Phys. Rev. B
arxiv created 2013/01/11 · openalex publication_date 2013/01/22 · arxiv updated 2013/01/24 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
We study the ground-state phase diagram of the frustrated quantum J1-J2 Heisenberg antiferromagnet on the honeycomb lattice using a mean-field approach in terms of the Schwinger boson representation of the spin operators. We present results for the ground-state energy, local magnetization, energy gap, and spin-spin correlations. The system shows magnetic long-range order for 0\ensuremath\leqslantJ2/J1\ensuremath\lesssim0.2075 (N'eel) and 0.398\ensuremath\lesssimJ2/J1\ensuremath\leqslant0.5 (spiral). In the intermediate region, we find two magnetically disordered phases: a gapped spin liquid phase, which shows short-range N'eel correlations (0.2075\ensuremath\lesssimJ2/J1\ensuremath\lesssim0.3732), and a lattice nematic phase (0.3732\ensuremath\lesssimJ2/J1\ensuremath\lesssim0.398), which is magnetically disordered but breaks lattice rotational symmetry. The errors in the values of the phase boundaries, which are implicit in the number of significant figures quoted, correspond purely to the error in the extrapolation of our finite-size results to the thermodynamic limit.