Wits University Pioneers Quantum Imaging and Secure Communication.

Researchers at the Wits University Structured Light Laboratory, led by Distinguished Professor Andrew Forbes from the School of Physics, are integrating classical optics, quantum physics, and artificial intelligence to advance secure communication and imaging technologies. The laboratory’s research is structured around three pillars: classical light manipulation utilising shaped laser beams, quantum light generation focusing on single photons and entangled particles, and bespoke laser development.

This approach has yielded a quantum camera capable of imaging through obscuring media, achieved by correlating photons transmitted through the medium with those detected by a conventional camera, reconstructing an image otherwise unattainable. Furthermore, the team is employing artificial intelligence and machine learning algorithms to develop cameras capable of both image acquisition and data interpretation, with potential applications in concealed weapon detection and non-invasive cancer cell identification. The laboratory’s comprehensive methodology encompasses the entire data pipeline, from structured light production to analytical understanding, facilitated by a supportive research environment at Wits University.

Structured Light Capabilities

Distinguished Professor Andrew Forbes, from the School of Physics, leads research leveraging this technique across diverse applications, including advanced imaging and secure communication. This involves shaping laser beams using techniques such as spatial light modulators and diffractive optical elements to encode information directly onto the light’s wavefront, creating beams with complex three-dimensional structures.

The laboratory’s expertise in classical structured light focuses on enhancing data transmission rates through increased spatial bandwidth. By encoding multiple data streams onto the complex spatial structure of a single laser beam, the team achieves higher data throughput compared to traditional communication methods.

This is achieved by precisely controlling the phase and amplitude of the light, creating beams with orbital angular momentum (OAM) or other complex spatial profiles, effectively increasing the ‘dimensionality’ of the communication channel. Complementing this classical approach is a significant focus on quantum light sources and their application to structured light imaging.

The team has developed a novel quantum camera capable of imaging through scattering media, such as living tissue or tinted glass, by exploiting the unique properties of single photons and entangled particles. A crucial element of the laboratory’s capabilities is the integration of artificial intelligence and machine learning algorithms into the imaging pipeline.

This allows for not only image acquisition but also automated data interpretation, facilitating applications of quantum key distribution (QKD) protocols, which leverage the principles of quantum mechanics to generate and distribute encryption keys with guaranteed security.