Multiferroic materials, in which electric and magnetic properties are combined in promising ways, will be the heart of new solutions for data storage, data transmission, and quantum computers. Meanwhile, understanding the origin of such properties at a fundamental level is key for developing applications, and neutrons are the ideal probe.
Neutrons possess a magnetic dipole moment which makes them sensitive to magnetic fields generated by unpaired electrons in materials. This makes neutron scattering techniques a powerful tool to probe the magnetic behavior of materials at atomic level.
The story of the so-called layered perovskites and the breakthrough results now published are a paradigmatic example highlighting both the role of fundamental studies in the development of applications and of the power of neutrons. Being a promising class of materials exhibiting coupled magnetic and electric ordering properties at ambient temperatures, the magnetic structure of the layered perovskites YBaCuFeO5—and thus the origin of their interesting magneto-electric behavior—was still to be unambiguously determined.