Single monolayer ferromagnetic perovskite SrRuO3 with high conductivity and strong ferromagnetism

Achieving robust ferromagnetism and high conductivity in atomically thin oxide materials is critical for advancing spintronic technologies. Here, we report the growth of a highly conductive and ferromagnetic single monolayer SrRuO3 (SRO) having a high Curie temperature of ∼ 154 K on DyScO3 (110) substrates. The SrTiO3 capping layer effectively suppresses surface reactions, which typically hinder ferromagnetism in atomically thin films. X-ray absorption spectroscopy and x-ray magnetic circular dichroism measurements revealed strong orbital hybridization between Ru 4d and O 2p orbitals in the SRO monolayer, which contributes to the enhancement of the conductivity and ferromagnetic ordering of both the Ru 4d and O 2p orbitals. The resistivity of the single monolayer SRO is comparable to that of the bulk SRO. This study highlights the potential of monolayer SRO as a platform for two-dimensional magnetic oxide systems, offering opportunities for the exploration of spintronic devices and quantum transport phenomena.