According to previous theoretical work, the binary oxide CuO can become a room temperature
multiferroic via tuning of the superexchange interactions by application of pressure. Thus far, however, there has been no experimental evidence for the predicted room-temperature multiferroicity.
Here, we show by neutron diffraction that the multiferroic phase in CuO reaches 295 K with the
application of 18.5 GPa pressure. We also develop a spin Hamiltonian based on density functional
theory and employing superexchange theory for the magnetic interactions, which can reproduce
the experimental results. The present study provides a stimulus to develop room-temperature
multiferroic materials by alternative methods based on existing low temperature compounds, such
as epitaxial strain, for tunable multifunctional devices and memory applications.
Materials by design for sustainable solutions in the energy, medical, transport, and engineering sectors
