Numéro
J. Phys. I France
Volume 1, Numéro 7, July 1991
Page(s) 1055 - 1062
DOI https://doi.org/10.1051/jp1:1991189
DOI: 10.1051/jp1:1991189
J. Phys. I France 1 (1991) 1055-1062

Fluctuation effect on the incommensurate transition of quartz

P. Borckmans, G. Dewel and D. Walgraef

Service de Chimie-Physique, Université Libre de Bruxelles, Bd du Triomphe, CP 231, B-1050, Brussels, Belgium


(Received 10 December 1990, accepted in final form 21 March 1991)

Abstract
In the mean field description of the incommensurate transition of quartz, the triangular 3- q, the striped 1- q and the $\beta$ phases meet at the same critical point. It is shown that critical fluctuations lift this degeneracy and transform the second order transition into first order ones. Furthermore, there is a regime of the parameter space where the 1- q phase should appear between the $\beta$ and 3- q phases, even in the absence of any applied stress, as seen in recent experiments.

Résumé
Dans la description au champ moyen de la transition vers les structures incommensurables du quartz, les phases 3- q, 1- q et $\beta$ apparaissent au même point critique. On montre que les fluctuations critiques lèvent cette dégénérescence et transforment la transition du second ordre en transitions du premier ordre. De plus, il existe une région de l'espace des paramètres où la phase 1- q apparaît entre les phases $\beta$ et 3- q, même en l'absence de tension appliquée, comme le montrent des expériences récentes.



© Les Editions de Physique 1991

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.