Strong localization of anionic electrons at interlayer for electrical and magnetic anisotropy in two-dimensional Y₂C electride

We have synthesized a single crystalline Y₂C electride of centimeter-scale by floating-zone method and successfully characterized its anisotropic electrical and magnetic properties. In-plane resistivity upturn at low temperature together with anisotropic behavior of negative magnetoresistance is ascribed to the stronger suppression of spin fluctuation along in-plane than that along the c-axis, verifying the existence of magnetic moments preferred for the c-axis.A superior magnetic moment along the c-axis to that along the in-plane direction strongly demonstrates the anisotropic magnetism of Y₂C electride containing a magnetically easy axis. It is clarified from the theoretical calculations that the anisotropic nature of the Y₂C electride originates from strongly localized anionic electrons with an inherent magnetic anisotropy in the interlayer spaces.