Peculiar Magnetic and Magneto-Transport Properties in a Noncentrosymmetric Self-Intercalated van der Waals Ferromagnet Cr₅Te₈

Trigonal Cr₅Te₈, a self-intercalated van der Waals ferromagnet with an out-of-plane magnetic anisotropy, has long been known to crystallize in a centrosymmetric structure. However, optical second harmonic generation experiments, together with comprehensive structural analysis, indicate that this compound rather adopts a noncentrosymmetric structure. Lorentz transmission electron microscopy reveals the presence of Néel-type skyrmions, consistent with its noncentrosymmetric structure. A large anomalous Hall conductivity of 102 Ω^-1cm^-1 at low temperature stems from intrinsic origin, which is larger than any previously reported values in the bulk Cr-Te system. Notably, spontaneous topological Hall resistivity arising from the skyrmionic phase has been observed. Our findings not only elucidate the unique magnetic and magneto-transport properties of noncentrosymmetric trigonal Cr₅Te₈, but also open new avenues for investigating the effects of broken inversion symmetry on material properties and their potential applications.