| dc.creator |
Cuccoli Alessandro |
|
| dc.creator |
Tognetti Valerio |
|
| dc.creator |
Roscilde Tommaso |
|
| dc.creator |
Verrucchi Paola |
|
| dc.creator |
Vaia Ruggero |
|
| dc.date |
2000 |
|
| dc.date.accessioned |
2013-05-30T00:25:37Z |
|
| dc.date.available |
2013-05-30T00:25:37Z |
|
| dc.date.issued |
2013-05-30 |
|
| dc.identifier |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332000000400011 |
|
| dc.identifier |
http://www.doaj.org/doaj?func=openurl&genre=article&issn=01039733&date=2000&volume=30&issue=4&spage=697 |
|
| dc.identifier.uri |
http://koha.mediu.edu.my:8181/jspui/handle/123456789/3086 |
|
| dc.description |
We study the two dimensional quantum Heisenberg antiferromagnet on the square lattice with easy-axis exchange anisotropy by the semiclassical method called pure-quantum self-consistent harmonic approximation. In particular, we focus on the problem of the existence of a nite-temperature transition in such a model, and study the corresponding critical temperature as the spin value and the anisotropy vary. We find that an Ising-like transition characterizes the model even when the anisotropy is of the order of 10-2J (J being the intra-layer exchange integral). The good agreement found between our theoretical results and the experimental data for the compounds Rb2MnF4, K2MnF4, and K2NiF4 shows that the insertion of the easy-axis exchange anisotropy, with quantum effects properly taken into account, provides a quantitative description and explanation of the real system's critical behaviour. |
|
| dc.publisher |
Sociedade Brasileira de Física |
|
| dc.source |
Brazilian Journal of Physics |
|
| dc.title |
The two-dimensional quantum Heisenberg antiferromagnet with Ising-like anisotropy |
|