Crystal Growth
PRIME is equipped with a state-of-the-art Floating Zone image furnace from Quantum Design. This device enables the growth of hiqh quality single crystals of oxides and metals for characterization and neutron scattering measurements. There are only a handful of universities in Canada that have similar facilities. Lower inset: the growth of a langasite single crystal.
DynaCool 9 T PPMS
Our new 9 T DynaCool Physical Property Measurement System from Quantum Design has the capability to measure the magnetic susceptibility, heat capacity, resistivity, and thermal conductivity down to 0.35 K. The entire system is run on a closed cycle liquid helium unit which conserves cryogens. The PPMS is open for use by all members of PRIME after commissioning is complete in 2012.
Neutron Scattering
X-ray and neutron scattering are very complementary techniques in the study of the properties of solids. X-rays are particularly well suited for the study of static properties of systems, since typical x-rays generated on conventional sources have energies on the order of several thousand electron volts, which is much greater than the average excitation found at room temperature in a particular material. Neutrons, on the other hand, have thermal energies on the order of meV, which is the energy range of lattice and spin excitations in solids. Therefore, neutrons scattering is a very powerful probe of both statics and dynamics in solids.
Bert Brockhouse
The neutron also has a property known as spin, which can interact with other magnetic moments within a material. Thus, neutron scattering can be used as a technique to probe magnetic structures and excitations as well as lattice structure and excitations (phonons). A famous neutron scatterer, Bert Brockhouse (a Nobel prize winning physicist) once commented that “If the God didn’t event the neutron, then we would have to.”
The "Golden Age of Neutron Scattering"
Neutron scattering has entered a “Golden Age” in the twenty-first century. The technique was developed over fifty years ago, and now, modern technology is being used to refine these methods and optimize performance. There are several new neutron scattering projects within North America that our group is involved with:
The SNS
The Spallation Neutron Source: This will be the premier location to do neutron science in North America. Officially the SNS is now up and running although many instruments are still under development. The neutrons are produced through collisions of protons with a stationary target, yielding pulses instead of a continuous source. We can use the information from the timing of these pulses, and the high flux, to complete experiments that have never been done before.
Canada has a particular involvement with the development of VULCAN, a new instrument geared towards industrial applications. Prof. Wiebe is involved with the development of several beamlines, including ARCS, SEQUOIA, and the new ZEEMANS spectrometer.
Canada has a particular involvement with the development of VULCAN, a new instrument geared towards industrial applications. Prof. Wiebe is involved with the development of several beamlines, including ARCS, SEQUOIA, and the new ZEEMANS spectrometer.
NIST
The NCNR Expansion at NIST: The neutron source at NIST is undergoing a rapid expansion to include a new guide hall with up to 5 new instruments. This NSF-funded facility is widely recognized as a NIST success story. Most of our experiments are now completed here.
Although NIST is now shut down for the upgrade, we look forward to more experiments completed here in the near future.
Although NIST is now shut down for the upgrade, we look forward to more experiments completed here in the near future.
Chalk River
The CNBC at Chalk River: This reactor based source in Canada is still one of the better places to conduct neutron science in North America. I am still hopeful that the cold neutron beam facility will be installed there in the near future. There is also a new opportunity for a scattering source in Saskatoon (even closer to Winnipeg!).