Sample Environment for Neutron Scattering at High and Low Temperatures at the McMaster Nuclear Reactor

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The purpose of this Research Tools and Instruments grant application is to acquire a new temperature-controlled sample environment that will enable neutron diffraction studies of materials at the McMaster Nuclear Reactor (MNR). We propose to purchase a closed cycle cryostat which will allow these measurements over an unusually broad dynamic range in temperature. This will allow researchers and their highly qualified personnel to investigate the structural and magnetic properties of materials from very low temperature (T ~ 2.7 K) to very high temperature (T ~ 800 K) in a single sample environment. ******Following the closure of the NRU reactor at Chalk River in March of 2018, the MNR became Canada's only source of neutron beams for materials research. Neutrons are an invaluable tool for studying the properties of materials, revealing unique and detailed information about both atomic and magnetic structure from the atomic scale to the mesoscale (tens of nanometers). The MNR is currently home to two neutron scattering beamlines: the McMaster Alignment Diffractometer (MAD) and the McMaster Small Angle Neutron Scattering beamline (MacSANS, which will become operational in Summer 2019). These two beamlines offer unique capabilities for materials research with neutrons in Canada, and have the capacity to serve scientists from across the country, in fields ranging from Physics and Chemistry, to Biology, Environmental Sciences, and Engineering. ******In order to fully exploit these unique capabilities, we require sophisticated sample environments which will allow us to study how materials of interest respond to conditions ranging from low temperatures (where quantum mechanics can give rise to exotic and unusual states of matter) to high temperatures well above room temperature (and where materials typically display a wealth of structural phase transitions and where materials of commercial and industrial interest often find their applications). A number of very topical research areas in the physics and chemistry of new materials, such as the study of thermoelectric materials and multiferroic materials, to name just two, display phenomena that requires diffraction studies across a broad range of temperatures. This new sample environment will allow our samples of interest to be studied across this range of temperature on a single platform, thus avoiding the complications of changing from a low temperature apparatus to a high temperature apparatus, and saving valuable beam time in the process. This RTI application will fund the purchase of a new sample environment from Advanced Research Systems, Inc. which has an operating temperature range of 2.7 K to 800 K. This proposed apparatus is fully compatible with both the MAD and MacSANS neutron diffraction instruments, opening up important new capabilities for parametric studies of materials over a very broad range of temperatures, and exciting new opportunities for Canadian materials researchers.**