Grant: Research Tools and Instruments

The field of high entropy materials (HEM) challenges traditional paradigms in condensed matter physics by exploring the properties that emerge from profound configurational disorder. This disorder, which arises from multiple elements sharing a single crystal lattice, imbues some HEMs with functional properties that far surpass their conventional counterparts, particularly in applications like energy storage and catalysis. However, key questions remain about the actual degree of configurational disorder, its role in stabilizing high entropy phases, and its impact on physical properties such as magnetism and electrical transport. A major hurdle in advancing the understanding of HEMs is the lack of single crystal samples, which limits the study of their anisotropic or collective properties. In existing polycrystalline samples, crucial information is averaged out due to the random orientation of structural grains. The growth of single crystals in HEMs is particularly challenging because it requires perfect chemical disorder. Floating zone growth, with its precise control of melting and crystallization, is the ideal method to unlock this new frontier. The Hallas Lab at UBC already houses two state-of-the-art floating zone image furnaces, but there are technical limitations that currently prevent their successful application to HEM growth. To address this, we propose acquiring a suite of four instruments to complement our existing furnaces, creating a comprehensive system for single crystal growth of HEMs. Specifically, we seek to acquire a ball mill and an arc-melter with suction casting to homogenize reagents and prepare feed rods for floating zone growth, a turbo-pump cart to create an air-free environment during crystal growth, and a crystal cutter with a goniometer for aligning and preparing high entropy crystals for measurement. These tools will be integral to the work of dozens of HQP annually and will be broadly available to external users. Expertise in sample preparation is a critical skill for experimental physicists, who are in high demand in Canada's burgeoning quantum technology sector. The ability to grow single crystals of HEMs will immediately enable several critical breakthroughs. For the first time, we will be able to measure intrinsic electrical and thermal transport properties, determine whether HEMs exhibit significant anisotropy, and study their collective excitations, including phonons and magnons. This last objective is especially important, as the dynamic properties of HEMs have been largely inaccessible. Whether the well-defined crystal lattices of these chemically disordered materials will exhibit well-defined dispersive excitations remains an unexplored frontier.