Research
We study organizing principles of mesoscale self-assembly phenomena that lead to creation of artificial materials and structures with emergent physical behavior and properties arising from the patterning of molecular order combined with the organization of nano- and micro-sized particles into precisely controlled configurations. These phenomena may enable technological breakthroughs in the development of flexible information displays, efficient conversion of solar energy to electricity, novel optically controlled materials capable, in turn, of controlling light, etc. The emergent scientific frontiers in these fields show an exceptional promise of significant new discovery becoming possible only now, after recent breakthroughs in different branches of science and technology. They require dealing with a hierarchy of length and time scales as well as inspiration and creation of entirely new concepts, laws, and generalizations. We pursue this study in a broad range of nano-structured soft matter systems, with the focus on fundamental aspects, such as the role that topology and geometry play in pre-determining self-assembly. The common theme that unites our research interests is the emergence of various degrees of (liquid crystalline) order as a result of the self-assembly. Examples of current research projects are described below.
Defects are responsible for many well-known processes: plastic deformations and fracture in metals are governed by dislocations, vortices in the atmosphere show up as tornadoes, disclinations in condensed Read more »
We combine topology and active matter paradigms in an effort to achieve topology-dictated nonequilibrium self-assembly of topologically distinct active particles. Active colloids are a distinct category of nonequilibrium matter in which energy uptake, dissipation and movement take place at the level of discrete microscopic constituents. They are known to provide types of self-assembly not accessible in traditional condensed matter systems, such as “living crystals” Read more »
Particles embedded in a liquid crystal can interact with each other via elasticity-mediated forces. We study how the host medium’s intrinsic order translates into the self-organization of Read more »
Our study shows that the self-assembly of photonic liquid crystal structures can be guided by laser Read more »
Bacteria often live in multicellular communities known as biofilms. Unlike their planktonic counterparts, bacteria in biofilms are encapsulated in an extracellular matrix, a complex mixture of macromolecules (including DNA). We use biophotonics and soft matter approaches to quantitatively explore interactions of cells with the extracellular polymeric matrix in the biofilms. Our group utilizes holographic laser trapping to manipulate Read more »
A wide variety of quantum field and condensed phase phenomena arise as a result of the existence of particle-like excitations of continuous fields Read more »
Since the origins of the mathematical knot theory, development of which was prompted by early attempts of understanding structure of atoms, knotted fields and vortices arise in superstring and quantum Read more »
Organic photovoltaic devices are poised to fill the low-cost niche in the solar cell market and have a potential option of being produced in the form of flexible films. However, power conversion efficiencies for organic materials remain low (~8%). In collaboration with NREL, we employ self-organization of organic molecules into ordered columnar discotic and lamellar phases in the effort to improve charge carrier mobility and efficiency of the organic PVs. This becomes Read more »
Being abundant in nature, colloids find increasingly important applications in science and technology, ranging from Read more »