Polarization Manipulation and Correction Device

At several workshops held at Oak Ridge National Laboratory (ORNL) over the past 5 years, members of several U.S. scientific communities stressed the need for an advanced capability for measuring slow molecular motions in complex fluids such as polymers and biomaterials. The technique preferred by these researchers is called Neutron Spin Echo (NSE). While there are two NSE spectrometers in the U.S., they do not match the performance available in Europe. Developing the technology to mimic the European instrumentation in the U.S. is expected to face a steep and relatively long learning curve unless an alternative can be found. With support from the STTR program, we have recently developed and built an apparatus called a radiofrequency (RF) flipper which can be used for a technique called Neutron Resonant Spin Echo (NRSE). In principle, this method could provide the same level of performance as the European NSE spectrometers and would be cheaper to build and operate. It would remove the necessity for U.S. facilities to develop the same technology base that Europe has built up over the past several decades. Until now, the NRSE method has not been competitive because it suffers from aberrations that no one has succeeded in correcting. Using computer simulation, we have shown that we can build a suitable correction magnet using the high-temperature superconducting technology that we have developed with past STTR funding. We seek to build a prototype, repurposing much of the equipment built under previous projects, to fully demonstrate that our correction element will work and put the U.S. on a straightforward path to realizing the goals of the scientific community for advanced instrumentation. By combining our developed RF flipper with an aberration correcting magnet, we can offer the U.S. research community a path to a high-resolution spectrometer for probing molecular motions in a variety of important materials such as polymers, biomolecules, and glassy systems. If successful, such instrumentation could be installed at neutron scattering facilities in the U.S. and worldwide. Given the lower cost and complexity of the system we envisage compared with traditional NSE spectrometers used in Europe, we expect several neutron centers to be interested in purchasing our technology.