The development of new superconductors, molecular magnets, spin electronic and magnetic nano-structures are at the forefront of condensed matter research. Polarized neutron scattering provides exceptional possibilities for detailed understanding of the mechanisms involved. Measurement of the vector properties of the neutron polarization provides a unique way of recovering the significant directional and phase information lost when only neutron intensities are measured. The changes in the direction of the neutron spin that take place on scattering by a magnetic dipolar field are highly dependent on their relative orientations and can be measured very precisely using neutron polarimeters. On the other hand, the Larmor precession of neutron spin in magnetic field allows attachment a “Larmor clock” to every neutron. Such a Larmor labelling opens the possibility for the development of “unusual” neutron scattering techniques, where the energy (momentum) resolution does not require the initial and final states to be well selected. This decoupling results in an extremely high energy (momentum) resolution that is not achievable in conventional neutron spectroscopy (diffraction) because of intolerable intensity losses.

Three main objectives of this PNT JRA are:

• to develop and to make widely available a new generation of key tools used for a precise handling of neutron polarization vector
• to develop a new generation of neutron scattering instruments, methods and devices based upon the Larmor labelling of neutrons
• to develop interdisciplinary contacts and establish hand-on facilities that will allow for scientists from different field of physics to learn powerful polarized neutron scattering technique

The PNT JRA will achieve its objectives by undertaking research and activities in three key areas:

1. 3-dimensional neutron polarimetry
2. Larmor precession based neutron scattering instrumentation
3. Training program for people interested in polarized neutron scattering theory and practice

Coordinator: Alexander Ioffe