Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

Behaviour of twist-bend nematic structure under a uniform magnetic field

Abstract : From the elastic point of view, the twist-bend nematic phase, (N-TB), has a ground state characterised by a spontaneous bend with a precession of the director n along the direction of an axis t. The tilt angle formed between the director n and the axis t gives rise to a heliconical structure with a nanometric helical pitch p. Using an elastic continuum theory recently proposed as an extension of the Frank energy for these materials, we investigate the influence of an external magnetic field on the pitch of the N-TB phase. For a material with positive magnetic susceptibility anisotropy, when the magnetic field H is perpendicular to t, it is shown that the pitch of the nematic director n precession increases with H, and at a critical value of it becomes infinite as in a cholesteric liquid crystal, that is, one gets a uniform orientation of n. Our results include the behaviour of a cholesteric under field as a limiting case, and are obtained in the simple case where is assumed as uniform throughout the sample.
Type de document :
Article dans une revue
Liste complète des métadonnées

https://hal-u-picardie.archives-ouvertes.fr/hal-03623378
Contributeur : Louise DESSAIVRE Connectez-vous pour contacter le contributeur
Soumis le : mardi 29 mars 2022 - 16:34:31
Dernière modification le : mardi 13 septembre 2022 - 16:16:25

Identifiants

Collections

Citation

R. S. Zola, R. R. Ribeiro De Almeida, G. Barbero, Ioannis Lelidis, D. S. Dalcol, et al.. Behaviour of twist-bend nematic structure under a uniform magnetic field. Molecular Crystals and Liquid Crystals, Taylor & Francis, 2017, 649 (1, SI), pp.71-78. ⟨10.1080/15421406.2017.1303598⟩. ⟨hal-03623378⟩

Partager

Métriques

Consultations de la notice

5