Criticality of an isotropic-to-smectic transition induced by anisotropic quenched disorder.
We report combined optical birefringence and neutron scattering measurements on the liquid crystal 12CB nanoconfined in mesoporous silicon layers. This liquid crystal exhibits strong nematic-smectic coupling responsible for a discontinuous isotropic-to-smectic phase transition in the bulk state. Confined in porous silicon, 12CB is subjected to strong anisotropic quenched disorder: a short-ranged smectic state evolves out of a paranematic phase. This transformation appears continuous, losing its bulk first-order character. This contrasts with previously reported observations on liquid crystals under isotropic quenched disorder. In the low temperature phase, both orientational and translational order parameters obey the same power law.
Chahine
Gilbert
G
Institut de Physique de Rennes, UMR 6251, Université de Rennes 1, 35042 Rennes, France.
Kityk
Andriy V
AV
Knorr
Klaus
K
Lefort
Ronan
R
Guendouz
Mohammed
M
Morineau
Denis
D
Huber
Patrick
P
D016880:Anisotropy; D003198:Computer Simulation; D050866:Liquid Crystals / Q000737:chemistry*; D008956:Models, Chemical; D044367:Phase Transition