High Frequency Cryogenics at Leeds and Manchester (Hi-CaLM) Facility

Context: The Universities of Leeds and Manchester have a rich collective history of pioneering research in electronic, photonic, and quantum materials. Through the Henry Royce Institute, the National Graphene Institute, the Bragg Centre for Materials Research and the Photon Science Institute, we deliver significant research leadership, infrastructure and capability open to, and accessed by, the UK academic and industrial communities. Demand for access to our growth and fabrication facilities is substantial and continues to increase as a result of our internationally leading ultrapure implanted silicon, topological insulator, 2D heterostructured, and magnetic materials programmes. This has led to an urgent need to establish aligned capabilities in high-frequency and very low temperature characterisation to underpin the growth, study and exploitation of next-generation advanced materials. Challenges Addressed: Low temperature characterisation (particularly <1K) is essential for investigating quantum coherence and entanglement in development of new quantum materials and technology architectures, and for exploring superconductivity, magnetism, and topology in new materials. Obtaining data on device and materials performance with sufficient timeliness that it can beneficially be fed back into simultaneous development and optimisation programmes is a critical challenge. This requires capacity in measurement systems that are integrated into the materials growth, implantation, and device fabrication capability. It is the purpose of Hi-CaLM to establish this capacity. Aims and Objectives: Our aim is to establish a regionally distributed, accessible, dilution refrigerator facility across the Universities of Manchester and Leeds with complementary high-frequency capabilities. Manchester will focus on megahertz-to-gigahertz frequencies, and Leeds on the gigahertz-to-terahertz range. Each of these requires a different experimental configuration and so cannot be achieved in a single system. The combined facility will strongly enhance the UK capacity for millikelvin high frequency studies of electronic, photonic and quantum materials, both supporting and leading to collaborations with UK academic and industrial users. Our specific objectives are: To establish a joint open-access facility, building sovereign capacity and capability in the interlinked fields of Quantum Materials, Quantum Devices, and Quantum Metrology. To provide an internationally unique one-stop-shop facility for the measurement of electronic and photonic materials and devices, capable of applying dc to terahertz frequency signals to samples held at millikelvin temperatures. To deliver the facility as a national capability, ensuring inclusive access that mitigates barriers which might otherwise lead to bias or exclusion of specific user groups. To validate the facility with proof-of-principle experiments in a range of application areas, ensuring its long-term sustainability through TRAC recoveries and the future research it will underpin. Potential Applications and Benefits: An extensive group of external users are already engaged with our current facilities and will access Hi-CaLM. Manchester and Leeds are uniquely placed to provide this facility jointly to the UK community owing to substantial (~£150M) investments at both Universities underpinning our growth, implantation, and processing facilities. It is now imperative to provide enough low-temperature measurement capacity to capitalise upon this. The two systems together will address a breadth of research ranging from the fundamental understanding and application of new materials systems, to the design, development and implementation of new computing architectures and quantum devices. The work directly enabled will span from studies of qubits in implanted semiconductors, building needed sovereign-capability in their measurement, to the spin-dynamics in magnetic/spintronic devices, key to future low-energy computing architectures, and to the fundamental investigation of “twistronics” in modified graphene.