A5031774229- Liquid Crystal Research Advancements
- Photonic Crystals and Applications
- Advanced Materials and Mechanics
- Micro and Nano Robotics
- Pickering emulsions and particle stabilization
- Orbital Angular Momentum in Optics
- Nuclear reactor physics and engineering
- Photonic and Optical Devices
- Nonlinear Dynamics and Pattern Formation
- Plant and animal studies
- Nuclear Physics and Applications
- Graphite, nuclear technology, radiation studies
- Plant Reproductive Biology
- Visual perception and processing mechanisms
- Nuclear Materials and Properties
- Surface Modification and Superhydrophobicity
- Metamaterials and Metasurfaces Applications
- Electrowetting and Microfluidic Technologies
- Monoclonal and Polyclonal Antibodies Research
- Surface Roughness and Optical Measurements
- Protein purification and stability
- Molecular spectroscopy and chirality
- Advanced Optical Imaging Technologies
- Surfactants and Colloidal Systems
- Nuclear and radioactivity studies
University of Ljubljana
2016-2025
Jožef Stefan Institute
2016-2025
University of Southern Denmark
2024
University of Trento
2024
Leiden University
2017
National Institute of Advanced Industrial Science and Technology
2015
University of Oxford
2010-2014
Centre of Excellence NAMASTE
2012-2014
Tehnološko raziskovalni center JUB
2008
The ability to generate regular spatial arrangements of particles is an important technological and fundamental aspect colloidal science. We showed that confined a few-micrometer-thick layer nematic liquid crystal form two-dimensional structures are bound by topological defects. Two basic crystalline were observed, depending on the ordering around particle. Colloids inducing quadrupolar order crystallize into weakly ordered structure, where particle interaction mediated sharing localized...
Tying knots and linking microscopic loops of polymers, macromolecules, or defect lines in complex materials is a challenging task for material scientists. We demonstrate the knotting topological chiral nematic liquid crystal colloids into links arbitrary complexity by using laser tweezers as micromanipulation tool. All with up to six crossings, including Hopf link, Star David Borromean rings are demonstrated, stabilizing colloidal particles an unusual soft matter. The classified quantized...
Abstract Phenomenological Landau–de Gennes modelling based on the free energy of nematic liquid crystal colloids is reviewed. Nematic phase, gradient order, and surface anchoring contributions to total are used. The numerical finite difference relaxation technique explained as an efficient tool for minimisation energy. Effects mesh allocation discussed. Various conceptually different colloidal structures calculated show universality model. Single particles, dipolar–quadrupolar dimers,...
The last years have witnessed remarkable advances in our understanding of the emergence and consequences topological constraints biological soft matter. Examples are abundant relation to (bio)polymeric systems range from characterization knots single polymers proteins that whole chromosomes polymer melts. At same time, considerable been made description interplay between physical properties complex fluids, with development techniques now allow researchers control formation interaction...
Applications for photonic crystals and metamaterials put stringent requirements on the characteristics of advanced optical materials, demanding tunability, high Q factors, applicability in visible range, large-scale self-assembly. Exploiting interplay between structural properties, colloidal lattices embedded liquid (LCs) are promising candidates such materials. Recently, stable two-dimensional configurations were demonstrated nematic LCs. However, question as to whether 3D structures can...
It has been predicted, but never confirmed, that colloidal particles in a nematic liquid crystal could be self-assembled by delocalized topological defects and entangled disclinations. We show experimentally theoretically dimers 1D structures bound defect loops can indeed created locally thermally quenching thin layer of the around selected particles. The entanglement provides strong stringlike binding, which is ten thousand times stronger compared to water-based colloids. This unique...
Frustration of chiral ordering is explored in cholesteric liquid crystal droplets with planar degenerate anchoring using numerical modeling. Droplets variable pitches are studied, demonstrating the role a gradually increasing pitch and corresponding equilibrium structures. All previously known structures identified but notable differences. The presented director fields complemented detailed description defect regions. characteristic half-diameter +2 disclination from previous studies found...
We present experimental and theoretical study of colloidal interactions in quadrupolar nematic liquid crystal colloids, confined to a thin planar cell. Using the laser tweezers, particles have been positioned vicinity other their determined using particle tracking video microscopy. Several types analyzed: (i) pair interaction, (ii) interaction an isolated quadrupole with chain, (iii) two-dimensional (2D) crystallite. In all cases, are order several 100k(B)T for 2 microm particles, which...
We explore the flow of a nematic liquid crystal in microfluidic channels with rectangular cross section through experiments and numerical modeling. The profile orientational show three distinct regimes weak, medium, strong as driving pressure is varied. These are identified by comparing polarizing optical microscopy solutions nematofluidic equations motion. relative stability related to de Gennes characteristic shear-flow lengths ${e}_{1}$ ${e}_{2}$, together channel's aspect ratio $w/d$....
Long-term stability of monoclonal antibodies to be used as biologics is a key aspect in their development. Therefore, its possible early prediction from accelerated studies major interest, despite currently being regarded not sufficiently robust. In this work, using combination (up 6 months) and first order degradation kinetic model, we are able predict the long-term 3 years) multiple antibody formulations. More specifically, can robustly behaviour protein at intended storage condition (5...
We study the interactions and directed assembly of dipolar nematic colloidal particles in planar cells using laser tweezers. The binding energies for two stable configurations a pair with homeotropic surface alignment are determined. It is shown that orientation particle can efficiently be controlled changed by locally quenching liquid crystal from laser-induced isotropic phase. interaction single chain determined between pairs chains studied. demonstrate self-assemble into two-dimensional...
In this Letter, we demonstrate that the symmetry of elastic interaction between dipolar and quadrupolar colloidal particles in nematic liquid crystal leads to a novel variety 2D "binary" crystals, which have not been observed any system. The dipolar-quadrupolar is highly anisotropic shows power-law dependence when approach each other along director field with pair-binding energy order several thousands k(B)T for 4 microm diameter colloids.
We present numerical modelling of colloidal particles in chiral nematics with cubic symmetry (blue phases) within the framework Landau-de Gennes free energy. The interaction potential a single, nano-sized particle -1/2 disclination line is calculated as generic trapping mechanism for cholesteric blue phases. shown to be highly anisotropic and have threefold rotational symmetry. discuss equilibration texture respect positions unit cell size phase. also describe how preservation liquid crystal...
We use numerical modeling to study the flow patterns of an active nematic confined in a cylindrical capillary, considering both planar and homeotropic boundary conditions. find that emerges not only along capillary axis but also within plane where radial vortices are formed. If topological defects imposed by conditions, they act as local pumps driving flow. At higher activity, we demonstrate escape into third dimension, indicating importance dimensionality materials. argue measuring...
The topology and geometry of closed defect loops is studied in chiral nematic colloids with variable chirality. colloidal particles perpendicular surface anchoring liquid crystalline molecules are inserted a twisted cell the thickness that only slightly larger than diameter particle. total twist structure cells parallel boundary conditions set to 0, $\ensuremath{\pi}$, $2\ensuremath{\pi}$, $3\ensuremath{\pi}$, respectively. We use laser tweezers discern number $\ensuremath{-}1/2$ entangling...
The formation of emulsions from multiple immiscible fluids is governed by classical concepts such as surface tension, differential chemical affinity and viscosity, the action surface-active agents. Much less known about emulsification when one components active thus inherently not constrained laws thermodynamic equilibrium. We demonstrate realization consisting in encapsulation an liquid crystal (LC)-like gel, based on microtubules kinesin molecular motors, into a thermotropic LC. These...
We show that colloidal superstructures could be assembled in mixtures of large and small particles dispersed a nematic liquid crystal. Using elastic interaction with the disclination lines we succeed to demonstrate how one can decorate topological matrix defect rings loops formed by an array particles. Our simulations this concept self-assembly nematics extended down nanoscale
Significance Topological defects play a defining role in systems as extensive the universe and minuscule microbial colony. Despite significant advances our understanding of topological their mutual interactions, little is known about formation dynamics across different material fields embedded within same system. Here, using nematic microfluidics test bed, we report how flow orientational emerge cross-talk with each other. Although discussed nematofluidic context, such multifield...
Abstract Fractals are remarkable examples of self-similarity where a structure or dynamic pattern is repeated over multiple spatial time scales. However, little known about how fractal stimuli such as surfaces interact with their local environment if it exhibits order. Here we show geometry-induced formation defect states in Koch nematic colloids, exhibiting better than 90% three orders magnitude the length scales, from micrometers to nanometres. We produce polymer Koch-shaped hollow...
We describe the flows and morphological dynamics of topological defect lines loops in three-dimensional active nematics show, using theory numerical modeling, that they are governed by local profile orientational order surrounding defects. Analyzing a continuous span loop profiles, ranging from radial tangential twist to wedge ±1/2 we show distinct geometries can drive material flow perpendicular or along segment, whose variation around closed lead net motion, elongation, compression shape,...