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Induction Furnace
An electrical furnace in which the heat is applied by inductive heating of a conductive medium (usually a metal) in a crucible around which water-cooled magnetic coils are wound.
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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.
Elastic scattering picture:
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.”
Bert Brockhouse, Nobel Prize winner (1994)
Inelastic scattering picture:
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 Spallation Neutron Source: This will be the premier location to do neutron science in North America, once it is online (end of 2006). 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.
- 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 (until the SNS comes online).
- 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.
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