School of Chemistry & Physics

BRICS Collaboration: Satellite and Fibre Based Quantum Communication Through a BRICS Collaboration we are developing a Quantum Satellite and fibre communication (QuSAF)Network in South Africa. 

The QuSaF project aims to establish a quantum network with a joint intercontinental satellite-based quantum key distribution link utilising the Micius satellite that the Chinese collaborators have already developed and launched into the lower earth orbital. The long-term vision for developing satellite quantum key distribution is the realisation of a quantum internet.

Furthermore, the project aims to establish a quantum fibre intercity communication link connecting four major cities in South Africa (Durban, Johannesburg, Pretoria and Cape Town). QuSaF will be South Africa’s first Quantum Satellite demonstration. BRICS Collaboration: Photonic Crystal Fibre The design of specialised fibre such as photonic crystal fibre (PCF) and micro structured optical fibres(MOFs) may provide opportunities for higher encoding for QKD. 

This research focuses on the few-mode effects during the process of transmitting optical signals via new PCF’s and MOFs, a modified structure, characterized by an enlarged core size and induced asymmetry of the hexagonal cross-section geometry, combined with chiral extremely enlarged core graded index optical fibres. This involves using machine learning in the design process and the guiding of higher dimensional optical modes. 

Quantum Optics, Dr Ismail’s group are experimenting on the development of single photon sources using the process of spontaneous parametric down conversions. Ther Group investigate the use of fully and partially spatially coherent bi-photons states for the use in quantum communication systems. Thier Group investigate the influence that varying atmospheric turbulence has on varying partial spatial coherent single photon sources.

Cold atoms, Their Group trap Rb87 atoms within a magneto optical trap to investigate light matter interaction between atoms and light fields such as those carrying orbital angular momentum.

The exchange of orbital angular momentum is of particular interest since it demonstrates the quantised transfer of the orbital angular momentum of a photon to an atom. In the long term the outcomes of such investigations will result in the implementation of high-dimensional quantum memories. The realisation of quantum memories in the long-run will be integral for the development of quantum technologies such as quantum repeaters.