A low-cost, direct fabrication technique with a micrometer range resolution has been implemented for rapid prototyping of optical masks for photolithography and structured light and diffraction optics applications. Using a setup based on the optical unit of a compact disc-digital versatile disc burner, a low-energy infrared laser beam was focused on a thin polymeric layer with embedded absorbing carbon nanopowder coated on a transparent glass substrate. This allowed for the generation of a custom-made transparent pattern in a computer numerical control fashion. In addition to its great simplicity and repeatability, the method also enables grayscale contrasts for each pixel individually, and fabricated masks proved to resist high intensities.

Abstract. In this paper we study the complexity of the nuclear states in terms of a two body quadupole-quadrupole interaction. Energy distributions and eigenvectors composition exhibit a visible interference pattern which is dependent on the intensity of the interaction. In analogy with optics, the visibility of the interference is related to the purity of the states, therefore, we show that the fluctuations associated with quantum chaos have as their origin the remaining quantum coherence with a visibility magnitude close to 5%.