Formation of optical energy flows using the biaxial crystal

摘要

We demonstrate a simple scheme for generation the internal energy flows in optical fields based on a biaxial crystal. Such fields offer a variety of possibilities for microparticles' trapping and control, for example: the intensity minima (maxima) due to the gradient forces; phase singularities are coupled with the vortex-like orbital flows; both the orbital and spin flows; the spin angular momentum density of the field may induce controllable spinning motion of particles; the output field pattern can be easily modified via the controllable input and output polarization, which provides suitable means for fine spatial positioning of the trapped particles.