Magnetic and electronic properties of EuMnSb₂ under high pressure

EuMnSb₂ is a magnetic topological Dirac semimetal candidate with large magnetoresistive behavior and exceptional electronic transport properties. The strong coupling of Eu moment with the charge transport offers a potential pathway to control topological properties. In this work, we have investigated the pressure tuning of magnetism, valence states, and crystal structure. Time-domain synchrotron Mössbauer experiments in ¹⁵¹Eu have been performed on EuMnSb₂ under quasihydrostatic pressure to investigate the evolution of local moment from the Eu sublattice. High-pressure angular-dispersive X-ray diffraction experiments were conducted to probe the change in crystal structure while X-ray absorption near edge structure experiments performed at Eu’s L₃-edge and Mn’s K-edge were used to examine valence states of Eu and Mn, respectively. We have documented remarkable changes in the magnetic properties and valence states under high pressure. The mechanism of these changes and their relation to the crystal structure will be discussed in detail.