Ferromagnetic semiconductors in extended lanthanide wires

Exploring one-dimensional (1D) ferromagnetic chains with high magnetic transition temperatures and robust spin polarization is crucial for the development of next-generation spintronic devices. Here, we demonstrate a bottom-up approach to the design and assembly of a 1D ferromagnetic chain based on the magic sandwich cluster Ho₂B₈. The stability of Ho₂B₈ is rationalized by the large HOMO-LUMO gap (2.02 eV) and double σ + π aromaticity. Our results show that the 1D linear chain is an attractive ferromagnetic semiconductor with the valence band fully spin-polarized. The long-range ferromagnetic order with a 5 μ_B magnetization on each Ho atom retains up to 86 K, and it features a magnetic transition within a tiny compressive strain (5%). Furthermore, the 1D linear chain exhibits a sizable magnetic anisotropy energy up to 30 meV/atom, indicating a sufficient energy barrier to suppress the spin fluctuations. The present findings suggest that the magnetic lanthanide chain (Ho₂B₈)_n is a prospective candidate for next-generation spintronic devices.