Frustrated antiferromagnets at high fields: the Bose-Einstein condensation in degenerate spectra
| dc.creator | Jackeli, G. | |
| dc.creator | Zhitomirsky, M. E. | |
| dc.date | 2003-12-02 | |
| dc.date | 2004-05-13 | |
| dc.date.accessioned | 2026-07-07T02:55:08Z | |
| dc.date.available | 2026-07-07T02:55:08Z | |
| dc.description | Quantum phase transition at the saturation field is studied for a class of frustrated quantum antiferromagnets. The considered models include (i) the $J_1$-$J_2$ frustrated square-lattice antiferromagnet with $J_2={1/2}J_1$ 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 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 $(π,π)$ and $(π,0,0)$ for the two models. The asymptotic behavior of the magnetization curve differs significantly from that of conventional antiferromagnet in $d$-spatial dimensions. We predict a unique form for the magnetization curve $ΔM=S-M\simeq μ^{(d-1)/2}(\logμ)^{(d-1)}$, where $μ$ is a distance from the quantum critical point. | |
| dc.description | minor changes; to appear in Phys. Rev. Lett | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0312076 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0312076 | |
| dc.identifier | Phys. Rev. Lett. 93, 017201 (2004) | |
| dc.identifier | doi:10.1103/PhysRevLett.93.017201 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/22831 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.subject | Statistical Mechanics | |
| dc.title | Frustrated antiferromagnets at high fields: the Bose-Einstein condensation in degenerate spectra | |
| dc.type | text |