The program has two distinct areas of activity 1) Diffractive optical elements, in particular photonic crystal films 2) Manipulation of nanoparticles with optical fields in waveguides The first area of activity is the largest, with two Ph.D. students fully suppported by the program, and involves the design, fabrication and characterization of tuneable optical filters based on diffractive optical structures, specifically 2-dimensional p hotonic crystal films like the ones already studied at Stanford University by the team members. Tuneability can be achieved by the use of two parallell films that can be moved relative to one another. One Ph.D. student will work on theory and design, an d one on fabrication and characterization. As much as possible of the experimental work will be done at MiNaLab in Oslo, but each of the two students will also spend half a year at Stanford, one working on simulations of EM field propagation, and one wor king on fabrication of the micromechanical structures and the photonic crystal films. The second area of activity is part of a research project started in 2001 at the University of Tromsø. Its objective is to manipulate, detect and sort nano- and micro-particles with the help of optical waveguides. Trapping and propulsion of polystyrene spheres of diameters above 3 µm have already been demonstrated. The planned activity under this research program is a transition from the micrometre-scale to the nanometre-scale for the diameter of the trapped particles.