Novel laser-driven ultraviolet light sources for free space communication

Interest in enhancing current wireless communication technologies is high in both the defence and civilian sectors, with Ultraviolet C radiation (UVC, 200-290nm) emerging as a promising candidate for non-line-of-sight communications. The appeal of UVC lies in its ability to scatter effectively in the atmosphere, allowing for the transmission of signals to receivers that do not have a direct line of sight to the transmitter.

This scattering effect, combined with the lack of solar background noise in the UVC band, enables the detection of low-level signals and supports the creation of secure, localized communication networks. Furthermore, the wide, unlicensed spectrum available in the UV band has the potential to support high-speed data services, potentially enhancing existing communication systems.

Despite its potential, the development of a practical UVC communication system faces significant challenges, primarily due to limitations in current technology for generating and detecting UVC light. Key issues include the efficient generation of UVC light, as many materials either absorb too much light or lack the necessary properties for effective nonlinear light conversion.

This gap highlights the need for advancements in materials science and optical engineering to identify and develop materials capable of efficient UVC light generation and detection.

This project will focus on developing new methods for generating UVC light using lasers, specifically through the exploration of cascaded nonlinear processes in crystals and enhanced nonlinear interactions in nanostructures and metasurfaces. These experimental approaches aim to address the current challenges of material absorption and the efficiency of nonlinear materials, paving the way for the practical application of UVC in communication systems.

The implications of this research extend beyond communication technologies. UVC light has potential applications in underwater sensor networks, offering a solution for high-speed, broadband communication that current technologies cannot provide. This is particularly relevant for the monitoring of subsea installations in industries such as oil and gas.

Additionally, the semiconductor industry, which relies on UV light for manufacturing processes, stands to benefit from advancements in UVC light generation, offering the possibility of improved efficiency and effectiveness in industrial applications.