Dynamic optical laser fabrication for engineering of quantum photonic devices

© 2019 SPIE. A range of high precision laser fabrication tasks can be implemented using a combination of ultrashort pulsed lasers and tight focusing with a high numerical aperture lens. These methods can create material modifications confined within three dimensions with sub-micrometer scales. Dynamic optical elements, such as deformable mirrors or liquid crystal spatial light modulators can enhance the performance of laser fabrication systems through adaptive beam control. We explain how these methods are being used to improve fabrication of photonic devices, through aberration correction and parallelization for three-dimensional structuring of materials. In particular, aberration correction enables precise focusing deep inside high refractive index materials, where refraction at the surface introduces spherical aberration that increases with focusing depth. This causes distortion of the focus and hence a reduction in precision and efficiency of fabrication. We have used adaptive laser fabrication to enable a range of devices: applications include waveguide circuits for quantum optics, waveguides and Bragg gratings in diamond, targeted creation of colour centres in diamond, novel polymer/liquid crystal structures and diamond-based radiation detectors. These devices for building blocks for applications in quantum optics and sensing.