Development of neutrons as entangled quantum probes

We recently completed an experiment on LARMOR at ISIS that proved that each individual neutron prepared for a Spin Echo Small Angle Neutron Scattering (SESANS) measurement is in a quantum state with its trajectory and its spin entangled. Entanglement is a property unique to quantum system that is fundamental to attempts to build quantum computers or to create unassailable cryptographic communications. We expect entangled neutrons to allow us to probe the entanglement of electrons in materials, a phenomenon that is hard to measure in any other way that is thought to be important for the properties of materials such as high-temperature superconductors and for so-called topological systems being considered for advanced computer memory applications. Our goal in this experiment is to continue to develop this novel quantum probe for situations we expect to encounter in real materials.