Welcome to the Soft Matter Laboratory

Liquid crystal optical microresonator on the cover of Nature Photonics. This kind of resonators developed in our laboratory possess large electric tunability and novel polarization properties.
(Nature Photonics 2009)

2D colloidal crystal assembled from left-handed escaped hyperbolic defect ring colloidal dimers in right-handed twisted nematic cell viewed between parallel polarizers.
(Phys. rev. lett. 2009)

Our current research is focused on:

• Self-assembly in nematic colloids. We use optical tweezers to manipulate colloidal particles in nematic liquid crystals and we measure the forces and potential of colloidal interactions, mediated by the nematic. The aim of our research is to understand how and why small particles assemble in regular 2D patterns, which may lead to interesting photonic applications in the future, such as 3D photonic crystals and metamaterials, self-assembled from solid particles in nematics. (PRL 2009, PRL 2008, PRL 2007, PRL 2007, Science 2006)

• Liquid crystal optical microresonators. We study the optical properties of small droplets of a nematic liquid crystal embedded in a polymer matrix. When the refractive index of the matrix is smaller compared to the droplet, Whispering Gallery Modes can be supported inside LC microdroplets. This is light, circulating in a cavity after bouncing from the walls due to total internal reflection. The WGM spectrum can be tuned by external electric field, which opens many interesting applications as add/drop optical switches, sensors, tunable lasers, etc. (Nature Photonics 2009)

• Metamaterials from nematic colloids. Nematic hierarchical colloidal superstructures are promising candidates for spontaneous formation of split-ring-resonators (SRR), known to generate negative magnetic response at the resonant frequency. We are exploring the physics and, in particular, the optics of colloidal superstructures in the nematic liquid crystals with applications to electric-field-controlled metamaterials. (PRE 2008)