Probing matter by Neutron Spin-Echo: A high-resolution spectroscopic technique that unveil dynamics of materials at mesoscale

Neutron Spin Echo (NSE) spectroscopy is high resolution neutron spectroscopy technique and one of the most powerful to study the fascinating realm of dynamic molecular processes in soft matter. NSE offers unique insights into the mobility of molecular species particularly suitable to investigate the slow cooperative motions at nanoscopic and mesoscopic scale. Typical applications include relaxation phenomena in networks and rubbers; interface fluctuations in complex fluids and polyelectrolytes; transport processes in polymeric electrolytes and gel systems, the molecular rheology of polymer melts. NSE has also extensive application in biophysics to examine collective motions in proteins, transport process through cell membranes and other lipid systems, and self-diffusion processes.

The ability to tag substructures using Hydrogen and Deuterium contrast variation to resolve the relevant timescales of dynamics on selected molecular items is a significant advantage of NSE compared to other high-resolution neutron techniques.



The SNS-NSE spectrometer at the BL-15 of the Spallation Neutron Source, Oak Ridge National Laboratory is the first NSE spectrometer installed at a pulsed neutron source. This makes it unique in construction and operation. Here we will highlight the strengths and peculiarities of the SNS-NSE, its history and operation along with significant examples of science results.