Grant: Research Tools and Instruments - Category 1 (<$150,000)

This proposal is for the purchase of a liquid helium plant for the Quantum Materials Laboratory, which combines the experimental groups led by Sawatzky and Damascelli at the University of British Columbia. A major part of the research effort is the growth of oxide thin films and heterostructures with molecular-beam- epitaxy methods, and the study of their electronic properties at liquid He temperatures. These systems belong to the class of quantum materials, which owing to their spectacular physical properties hold great promise for technological application in modern electronics and spintronics. A crucial step is that of characterizing the electronic properties with in-situ transport and photoelectron spectroscopy techniques. Since quantum mechanical phenomena in solid-state materials are smeared out when the temperature of the system rises above 4 degrees Kelvin (e.g., superconductivity, superfluidity, Josephson effect, quantum Hall effects), this requires performing extensive experimental work at liquid He temperatures. For this reason, Sawatzky and Damascelli must cool their measurement equipment down to about 4K, and for this they must use liquid He flow cryostats, as opposed to close-cycle systems that would generate vibrations incompatible with the sensitive measurements to be performed. Unfortunately, with continuous flow systems liquid helium rapidly boils away, and if the evaporated gas is not collected it is lost in the atmosphere. This is both extremely costly and not environmentally viable: Helium is a crucial commodity for modern science, technology, and industry, with the largest single use being medical imaging in MRI facilities. However, the supply of this key resource for cryogenic applications is dwindling. At present, the Quantum Materials Laboratory as a whole is spending approximately $100,000/year to consume one of the earth's most precious and nonrenewable resources, releasing it into the atmosphere to escape into space. This RTI proposal aims at providing a sustainable source of liquid He through the purchase of a plant that will allow recovering and reliquefying the He on site, at 15% of the commercial cost.