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A. M. Parshin^1,2, V. G. Nazarov², V. A. Gunyakov^1,2, V. Ya. Zyryanov^1,2,3, V. F. Shabanov^1,2,3

Author affiliations
¹Kirensky Institute of Physics, Krasnoyarsk Scientific Centre, SB RAS
Krasnoyarsk 660036, Akademgorodok 50, Russia. 
E-mail: parshin@iph.krasn.ru
²Siberian Federal University,
Krasnoyarsk 660041, 79 Svobodny prospect, Russia
³M. F. Reshetnev Siberian State Aerospace University
Krasnoyarsk, 660014, 31 Krasnoyarsky rabochy prospect, Russia

Abstract
The structural transition within the nematic liquid crystal droplets of 4-n-pentyl-4'-cyanobiphenyl (5CB) and 4-n-pentyl-4'-cyanophenyl-cyclohexane (5PCH]) encapsulated in polyvinylbutyral matrix under magnetic field is reviewed. The nematic 5CB droplets formed under magnetic field H^* < 4 кOe as well as the 5PCN droplets formed under H^* < 5 кOe possess the classical bipolar structure. If H^* > 4 kOe, the uniform and radial structures are observed also in ensemble of the 5CB droplets. A tendency to align the bipolar axes along the field is revealed within the 5PCN droplets formed under H^* > 5 kOe. The radial structures inside the 5PCN droplets are absent. The spontaneous cyclic transition between the bipolar director configuration and homogenous structure can occur within the droplets in the temperature ranges t = (24 ÷ 34)^oС for 5CB as well as t = (32 ÷ 54) ^oС for 5PCN. Moreover the second variant of structural transition: bipolar configuration – radial one is discussed.

Keywords: polymer dispersed liquid crystal, nematic droplet, director configuration, magnetic field, structural transition