Collective excitations in two-dimensional antiferromagnet in strong magnetic field
| dc.creator | Syromyatnikov, A. V. | |
| dc.date | 2008-08-15 | |
| dc.date | 2009-02-12 | |
| dc.date.accessioned | 2026-07-07T12:40:15Z | |
| dc.date.available | 2026-07-07T12:40:15Z | |
| dc.description | We discuss spin-$\frac12$ two-dimensional (2D) Heisenberg antiferromagnet (AF) on a square lattice at T=0 in strong magnetic field H near its saturation value $H_c$. A perturbation approach is proposed to obtain spectrum of magnons with momenta not very close to AF vector in the leading order in small parameter $(H_c-H)/H_c$. We find that magnons are well-defined quasi-particles at $H>0.9H_c$ although the damping is quite large near the zone boundary. A characteristic rotonlike local minimum in the spectrum is observed at ${\bf k}=(π,0)$ accompanied by decrease of the damping near $(π,0)$. The suggested approach can be used in discussion of short-wavelength excitations in other 2D Bose gases of particles or quasi-particles. | |
| dc.description | 8 pages, 5 figures. Final version | |
| dc.identifier | https://arxiv.org/abs/0808.2127 | |
| dc.identifier | http://arxiv.org/abs/0808.2127 | |
| dc.identifier | Phys. Rev. B 79, 054413 (2009) | |
| dc.identifier | doi:10.1103/PhysRevB.79.054413 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/219389 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.subject | Statistical Mechanics | |
| dc.title | Collective excitations in two-dimensional antiferromagnet in strong magnetic field | |
| dc.type | text |