Ferroelectric switching and multiferroic behavior of wurtzite transition-metal chalcogenides

Wurtzite ferroelectrics have emerged as promising candidates for next-generation nonvolatile memories due to their large spontaneous polarization, CMOS compatibility, and potential for high-speed operation. Recently, wurtzite-type MnX (X = Se, Te, S) compounds have been identified as potential ferroelectrics that also host antiferromagnetic order. In this work, we investigate the crystal structures, microscopic mechanisms of polarization switching, and the stability of antiferromagnetic ground states in these MnX multiferroics. Using density functional theory (DFT), we compute the spontaneous polarization and obtain its magnitude of 43–55 μC/cm² oriented along the hexagonal [0001] axis. The estimated coercive field for uniform polarization switching (1.8–2.1 MV/cm) is comparable to the theoretical value for classical BaTiO₃, suggesting that polarization reversal is experimentally achievable. Domain-wall–mediated switching pathways reduce the energy barrier by approximately 40%, providing a more energetically favorable reversal mechanism. Our calculations further reveal multiple magnetic configurations in MnX, including antiferromagnetic and altermagnetic states. These results identify a family of novel multiferroic materials that hold potential for nonvolatile memory and magnetoelectric device applications.