tailieunhanh - Ferroelectrics Physical Effects Part 13

Tham khảo tài liệu 'ferroelectrics physical effects part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 470 Ferroelectrics - Physical Effects Yoshizawa A. Nishiyama I. 1995 . Interlayer Correlation in Smectic Phases Induced by Chiral Twin Molecules. Mol. Cryst. Liq. Cryst. Vol. 260 pp. 403-422 ISSN 15635287. 20 Memory Effects in Mixtures of Liquid Crystals and Anisotropic Nanoparticles Marjan Krasna1 Matej Cvetko1 2 Milan Ambrozic1 and Samo Kralj1 3 University of Maribor Faculty of Natural Science and Mathematics 2Regional Development Agency Mura Ltd 3Jozef Stefan Institute Condensed Matter Physics Department Slovenia 1. Introduction For years there is a substantial interest on impact of disorder on condensed matter structural properties Imry Ma 1975 Bellini Buscaglia Chiccoli 2000 Cleaver Kralj Sluckin Allen 1996 . Pioneering studies have been carried out in magnetic materials Imry Ma 1975 . In such system it has been shown that even relatively weak random perturbations could give rise to substantial degree of disorder. The main reason behind this extreme susceptibility is the existence of the Goldstone mode in the continuum field describing the orienational ordering of the system. This fluctuation mode appears unavoidably due to continuous symmetry breaking nature of the phase transition via which a lower symmetry magnetic phase was reached. For example the Imry Ma theorem Imry Ma 1975 one of the pillars of the statistical mechanics of disorder claims that even arbitrary weak random field type disorder could destroy long range ordering of the unperturbed phase and replace it with a short range order SRO . Note that this theorem is still disputable because some studies claim that instead of SRO a quasi long order could be established Cleaver Kralj Sluckin Allen 1996 . During last decades several studies on disorder have been carried out in different liquid crystal phases LC Oxford University 1996 which are typical soft matter representatives. These phases owe their softness to continuous symmetry breaking phase transitions via which these phases are reached on .