Unveiling the structure and formation of quantum materials via x-ray diffraction with non-ambient temperature stages

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The remarkable magnetic and electronic properties of quantum materials are inextricably linked with their underlying crystal symmetries. These crystal symmetries, both the space group of the crystal lattice and the point group symmetries of the ions inhabiting that lattice, determine what types of exotic states might emerge at low temperature (e.g. topological electronic states, quantum spin liquids, or unconventional superconductors). Structure determination via x-ray diffraction is thus the crucial first step in characterizing any new material grown in the Quantum Materials Design Lab. The vast majority of laboratory x-ray diffractometers, including ours, can only be operated at room temperature - greatly limiting their utility. The inability to perform x-ray diffraction measurements at high and low temperatures hinders our progress in two distinct ways: (i) some materials will undergo a structural phase transition below room temperature, and hence we lack the essential structural knowledge to understand its low-temperature quantum state, and (ii) the synthesis of some materials require a fine-tuned temperature profile and studying their formation in-situ is the only efficient way for us to deduce the appropriate conditions. Obtaining the data to answer these questions currently requires us to acquire beam time at a synchrotron x-ray or neutron facility. This process can take 6-12 months to complete, dramatically slowing the progress of our research and, at times, rendering projects infeasible. We propose to acquire a low-temperature (liquid nitrogen, down to -180 C) and a high-temperature (furnace, up to 1300 C) sample stage for our state-of-the art Bruker D8 Advance powder x-ray diffractometer, dramatically expanding its utility. Our diffractometer is a newly installed system expected to have a useful lifetime of up to 20 years with best-in-class resolution and sensitivity. Thus, we can study very small samples as well as samples with very subtle structural distortions. The two temperature stages we propose to acquire are completely modular in design, sharing many overlapping components, and as such, the cost of acquiring both is a marginal increase over acquiring either one individually. The long-term sustainability of this equipment will be ensured by establishing robust training protocols, standard operating procedures, and a regular maintenance schedule These two stages will enable us to better control the synthesis of materials discovered in our lab and to better understand the interplay of their quantum behaviors with their crystal symmetries. They will be an integral component of the projects of approximately 15 trainees (undergraduate, graduate, and postdoctoral) per year. Expertise with non-ambient sample environments is a critical skill for experimental physicists, who are in high demand for Canada's burgeoning quantum technology sector.