2003/12/31 by George Jackeli, G. Jackeli, M. E. Zhitomirsky · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.93.017201
published as Phys. Rev. Lett. 93, 017201 (2004) · minor changes; to appear in Phys. Rev. Lett
arxiv created 2004/05/13 · openalex publication_date 2004/07/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Quantum phase transition at the saturation field is studied for a class of frustrated quantum antiferromagnets. The considered models include (i) the J1\mathrm\text\ensuremath-J2 frustrated square-lattice antiferromagnet with J2=(1)/(2)J1 and (ii) the nearest-neighbor Heisenberg antiferromagnet on a face centered cubic lattice. In the fully saturated phase the magnon spectra for the two models have lines of degenerate minima. Transition into a partially magnetized state is treated via a mapping to a dilute gas of hard-core bosons and by complementary spin-wave calculations. Momentum dependence of the exact four-point boson vertex removes the degeneracy of the single-particle excitation spectra and selects the ordering wave vectors at (\ensuremathπ,\ensuremathπ) and (\ensuremathπ,0,0) for the two models. We predict a unique form for the magnetization curve \ensuremathΔM=S\ensuremath-M\ensuremath≃\ensuremathμ^(d\ensuremath-1)/2(log\ensuremathμ)^(d\ensuremath-1), where \ensuremathμ is a distance from the quantum critical point.