Exchange gas cryostat system for electrical characterization of materials at low temperatures

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In the last 30 years, there has been a rising interest for new families of superconducting materials, these materials that conduct electricity without resistance at low temperatures (around -200 degrees Celsius). Superconductors are now getting mature and will soon be present in numerous commercial products. The performance and the economics of the applications strongly depends on the electrical and mechanical properties of these materials, which are highly function of temperature and magnetic field. Thus, a prerequisite to achieve an efficient technological use of superconductors is to acquire a detailed knowledge of their physical properties. The Laboratory of Superconductivity and Magnetism (LSM) of Polytechnique Montreal advances the science and technology of superconductivity and particularly its applications in various fields, namely energy, transportation and biomedical. Its research program is unique in Canada owing to its focus on the characterization of commercial superconducting materials (large-scale samples) that are used in a wide range of emerging applications, for instance loss-free power transmission cables. The equipment asked for in this proposal is a variable temperature cryostat system capable of cooling superconducting samples at temperatures between 4.2 K (-269 Celcius) and room temperature, in order to support research in applied superconductivity, carried out with local and international partners. More specifically, the new equipment will allow performing two main types of experiments: 1) transport current measurements, and 2) magnetization measurements. The first type of experiment is very demanding in terms of cooling power. This led us to choose an exchange gas cryostat technology. Note that the new equipment will replace a former one that has reached its end of life. The new cryostat will also be compatible with the existing laboratory instrumentation and electromagnets, and it will improve substantially the range of temperature at which the characterization of superconductors can be performed in the current research program. It will also support research in emerging topics like 1) high-field magnets based on high temperature superconducting wires, and 2) synergetic action of liquid hydrogen and superconducting devices for greener aviation. That will put Polytechnique Montreal and the LSM in a unique position worldwide regarding the characterization of superconductors and should fulfill all research and training needs for the next 10 to 15 years. Among the practical impacts of the projects that will be carried out with the equipment requested, one can cite: 1) new types of cancer treatments using magnetic steering of drugs in blood arteries, 2) the development of electric propulsions systems for greener aircrafts, 3) the generation of very high magnetic fields to use in medical imaging, particle accelerators (for research in high-energy physics), nuclear fusion, etc.