Adaptive optics for Quantum Communications

Atmospheric turbulence perturbs optical signals, causing fading transmission, noise and degrading the quality of an optical  channel. Adaptive Optics (AO) is a technology developed for astronomical instrumentation and laser propagation to correct an image after the transmitted light has travelled through turbulent media. We are applying these AO techniques to free-space optical quantum communication. Modern telecommunications have revolutionised the way we communicate, and new techniques in quantum communication can provide information theoretically secure ways to communicate such as quantum key distribution (QKD). To achieve long range quantum communication such as inter-continental, quantum communications will require the use of free space optical links to/from Low Earth Orbit (LEO) satellites. 

The aim of our program at ANU is to develop AO equipped optical instruments to enable a satellite Continuous Variable QKD (CV-QKD) network. The ANU have been developing AO for free space optical communications. A compact demonstrator system has been built and tested over short horizontal distances to further develop the application of AO to optical communications.

We are looking for a motivated PhD student to join our team working on Advanced AO for Quantum Satellite Communication at ANU in the Research School of Astronomy and Astrophysics (RSAA). The program will contribute towards building Australia’s own satellite-to-ground optical link. This work will be carried out in collaboration with 

RSAA, the Research School of Physics and Engineering (RSPE) and the Defence Science and Technology Group (DST Group). A background in physics or related engineering course is a requirement and keen interests in optical instrumentation, adaptive optics, digital signal processing, communications, control system and/or quantum optics are highly desirable. There is the potential for opportunities to visit our collaborators at DLR in Germany and NICT in Japan.

In this PhD project you will investigate the use of AO in a horizontal free space laser link and be a key person in the implementation of a point-to-point CV-QKD free space link. You will develop a prototype system in the lab and work closely with other members of the team to develop the AO and free space optics. The final goal will be to demonstrate a positive key rate over a horizontal free space channel as an analogue of satellite-to-ground communication.

This three-year PhD position is sponsored by the Department of Defence’s DST Group based in Adelaide (see www.dst.defence.gov.au). The candidate must be an Australian citizen prior to the commencement of the PhD, and have been awarded the equivalent of a First Class Honours degree in Engineering or Physics. Prospective students will be expected to obtain an RTP or equivalent scholarship, and may be awarded a DST Group $5,000 per annum top-up scholarship in addition to travel and conference funds bringing the total stipend up to $50,000 for studies and travel.