Quantum materials

Discovering, understanding and engineering materials is central to the future of quantum technologies, providing the building blocks necessary for creating advanced quantum devices, preserving delicate quantum states and enabling quantum effects such as coherence. Entanglement requires highly refined material properties, including high material purity, defect-free crystal lattices, and pristine crystal surfaces and interfaces. Efficiently encoding, reading out and controlling quantum devices requires integration of multiple functionalities on the same chip, calling for a sustained and multi-disciplinary approach.

Our work in this area develops in two directions:

Firstly, we exploit different materials to engineer high-performance quantum devices: ranging from bright single photon sources, based on established III-V semiconductors; quantum memories, based on crystals doped with rare-earth ions; spin-photon interfaces, integrated in silicon carbide opto-electronic devices; to quantum sensors made of diamond.

Our Nanofabrication Cleanroom enables us to fabricate micro/nano-scale structures, which are characterised in our state-of-the-art labs and deployed for applications including quantum networking and quantum sensing.

Secondly, we engineer and probe new quantum materials in novel 2D devices. Since the discovery of graphene, obtained by peeling off sheets only a single atom in thickness from graphite, researchers have discovered remarkable properties in a variety of 2D materials, including semiconductors, insulators, metals and superconductors. These 2D layers can be re-assembled, atomic layer by atomic layer, into myriad configurations of different “heterostructures”, enabling tailoring of specific materials properties at will. These structures enable explorations of how strong particle interactions lead to emergent macroscopic physical effects that may lead to next-generation "beyond-silicon" electronic devices.

Long-term applications of our fundamental investigations could be, for example, Mott transistors, where the gate voltage would switch the device between insulating and conducting states with a much better efficiency than current devices. Or providing insights into high-temperature superconductivity and exotic types of magnetism with enormous potential for application. Our research into quantum effects in 2D heterostructures capitalises on a variety of techniques, from optical spectroscopy to the use of in-situ quantum sensors, to probe the properties of these devices down to atomic length scales.

We are part of four of the five new quantum Hubs, established by the UKRI Engineering and Physical Sciences Research Council (EPSRC) to ensure the UK benefits from the potential of quantum technologies. Heriot-Watt leads the “Integrated Quantum Networks Hub” (IQN) and is involved in the UK Hub for Quantum Enabled Position Navigation and Timing (QEPNT), The UK Quantum Technology Research Hub in Sensing, Imaging and Timing (QuSIT) and the UK Quantum Biomedical Sensing Research Hub (Q-BIOMED). Industry collaboration is key to these hubs, leveraging cash and in-kind contributions from partners worth more than £54 million.

The Institute of Photonics and Quantum Sciences (IPaQS) is part of a focused research ecosystem at Heriot-Watt University, working to tackle some of the world’s most pressing challenges. By bringing together experts in quantum technologies and photonics, IPaQS fosters a collaborative environment where innovative solutions can be developed. This interdisciplinary approach is strengthened through external partnerships, ensuring the research not only advances scientific understanding but also delivers real-world impact across multiple sectors.