Revealing the altermagnetic phase of α-Fe2O3 by angular-dependent in-field Mössbauer spectroscopy on single crystals

Recent theory and experimental investigations reveal the presence of a new magnetic phase called altermagnets. Altermagnets possess features that are normal characteristics of either antiferromagnets or ferromagnets and retain fascinating properties like high even-parity wave magnetism, generally associated with unconventional superconductivity. Within this proposal, we want to investigate the predicted altermagnetic phase in α-Fe2O3 utilising nuclear forward scattering. We expect that by our experimental protocol, we will have a spectroscopic tool to investigate altermagnetic materials with Mössbauer active isotopes. In addition, investigating high even-parity wave magnetism might help further understand the connection between unconventional superconductivity and magnetism.