A combination of thermophoresis and fluid flow can be used to trap molecules and particles. We showed that heating by scanning motion of an elongated laser spot creates a strong thermal trap. Additionally, it induces a global fluid flow that feeds the trap. Such “thermal sieve” can accumulate molecules from a large surrounding region within seconds into a 10 μm spot. Numerical modeling gives a quantitative prediction of the effect. Traps can be dynamically created, relocated, and tuned, which can be used for the creation of a "molecule sieve" which can spatially sort nanoparticles and molecules.
COBISS.SI-ID: 28423207
We demonstrated a new method for the realignment of nematic liquid crystals in already assembled cells with a focused IR laser beam. The heat generated by the IR absorption locally melts the liquid crystal and creates an isotropic island with well-defined molecular anchoring at the nematic–isotropic interface. Scanning motion of the the laser beam along a pre-defined line leaves behind a well oriented LC domain.
COBISS.SI-ID: 28524839