Project designed to take advantage of the world leading expertise at Heriot Watt in the technology of ultrafast laser inscription – a laser writing technology that facilitates the fabrication of three-dimensional optical waveguides inside dielectric materials. The primary goal is to develop 3D integrated multiport interferometers for state elimination measurement in quantum optical fibre communications systems. Such components offer considerable benefits over bulk optic systems, including stability, compactness and manufacturability, with higher throughputs than are currently achievable with other integration platforms e.g. silicon-on-insulator. A secondary and higher risk aim is to investigate the feasibility of developing mode-coupling and sorting components based on “photonic lanterns”, for the implementation of space-division-multiplexed quantum communications (both free-space and optical-fibre based). These components can then be used in different communications links, including potential free-space applications with an eye to communicating with orbiting satellites.