10032658ADRENALIN (lAser Diodes in the veRy nEar iNfrared for quantum AppLIcatioNs )ClosedCollaborative R&DISCFQuantum computing is a rapidly emerging technology offering transformative changes to society as a whole by providing vast improvements in computational capability that will solve complex many-body problems that are currently intractable. It will potentially deliver advancements in diverse fields such as finance, climate change, infrastructure planning, drug discovery, secure communications and material science. Trapped-ion Quantum Computing (TIQC) systems are one of the most advanced and promising quantum computing platforms in which an oscillating electric field is used to confine ions which serve as the qubits used to encode quantum information. This approach offers a route towards scaling up the number of qubits and thereby delivering the increase in computing power that is ultimately desired, allowing the technology to emerge from small scale lab-based experimental environments to integrated user-friendly systems for everyday use. Laser sources are a key requirement in TIQC, performing essential system functions including ionisation, cooling, repumping and spectroscopy. Typically these different requirements are served by a wide range of laser sources, each with different wavelengths and performance requirements. The ADRENALIN project will develop a novel type of laser, a Photonic Crystal Surface Emitting Lasers (PCSEL) for use in QT applications. PCSELs employ photonic crystals to produce 2nd order out-of-plane diffraction and enable vertical, single-frequency emission. This novel device architecture provides excellent beam quality compared to other laser diodes and significantly reduces manufacturing costs. PCSELs can also be configured in 2D arrays with steerable individually addressable output, enabling different lattice sites to be addressed simultaneously. In addition these devices can be manufactured in most III-V semiconductors, allowing most of the wavelength range used in QT applications to be addressed. The many advantages of the PCSEL device will help facilitate scaling in next generation TIQC systems to accommodate larger numbers of qubits thereby enabling exponential increases in computational power and more widespread utilisation of the technology. The PCSEL will also help drive miniaturisation in QT applications -- this is important in TIQC but is also a key driver in the development of miniature atomic clocks for portable high-precision time-keeping, enabling a more widespread adoption of the technology and providing the potential to significantly advance improvements in transportation, defence and communication sectors. In both applications, PCSELs will ultimately displace incumbent light sources which typically rely on relatively bulky, expensive and complicated external cavity lasers and will become essential components in future QT systems.