Publications by authors named "P V Dolganov"
Article Synopsis
- Researchers created "necklaces" of topological defects by manipulating opposite charges in nematic films and studied their movement and changes.
- The formation of these defects was influenced by temperature and competing surface anchoring at different interfaces, which altered the Euler characteristic of the system.
- As the geometry of the nematic changed, the arrangement of defects shifted from circular chains to single defects and eventually to a defect-free state, with distinct behavior observed in their evolution compared to traditional coarsening in 2D and 3D systems.
The dynamics of quasi-two-dimensional coalescence of isotropic droplets in nematic liquid crystal environment was studied. Investigations were made in confined geometry of a Hele-Shaw optical cell with different transverse droplet sizes. The existence of three distinct dynamic regimes was found for coalescence, namely, short-, middle-, and long-time regimes.
View Article and Find Full Text PDFStatics and dynamics of point boojums, line and modified Saturn ring topological defects in nematic confined geometry.
Eur Phys J E Soft Matter
December 2023
In this paper we study the static structure and the dynamics of topological defects associated with isotropic droplets in nematic environment. Investigations were made in confined geometry of optical cells when the droplet size was of the order of or larger than the gap of the cell. We observed the coexistence of point boojums and Saturn ring or modified Saturn ring defects.
View Article and Find Full Text PDFFocal conic structure formed near the transition from the cholesteric liquid crystal phase into isotropic liquid is studied in planar cells with a combination of optical methods. Employing a procedure with slow variation of temperature, we manage to obtain regions of periodic focal conic structure with two-dimensional square ordering in the plane of the cell. Using ordered samples and materials with selective reflection in the visible spectral range, we obtain spectral and microscopic optical data which deepen our knowledge of the focal conic structure.
View Article and Find Full Text PDFArticle Synopsis
- The study examines how nematic droplets merge in an isotropic environment and vice versa within a flat optical cell setup.
- Two distinct coalescence behaviors were identified: one involving the formation of both nematic and isotropic bridges, particularly with nematic droplets at the cell surfaces, and the other involving isotropic droplets coalescing from the center.
- The research highlights the instability of the outer bridge in nematic droplet coalescence, leading to satellite droplet formation, while isotropic droplet coalescence occurs smoothly without such instability or satellite droplets, illustrating a new example of Rayleigh-Plateau instability.