Hydrogen Evolution Driven by Photoexcited Entangled Skyrmion on Perovskite Ca₂Na_n-3Nb_nO_{3 n+1}Nanosheet

A magnetic skyrmion is a topologically stable state with potential applications for realizing the next-generation spintronic devices. Here, we demonstrate the real-space observation of skyrmions in Dion-Jacobson phase perovskite, Ca2Nan-3NbnO3n+1- (CNNO), nanosheets by using optical injection. The CNNO4 and CNNO6 nanosheets exhibit weak ferromagnetics, while the CNNO5 nanosheet is superparamagnetic. The magnetic skyrmion can be clearly observed in those 2D nanosheets in the absence of the external magnetic field. First-principles calculations and micromagnetic simulations predict that the magnetic skyrmions in CNNO nanosheets is Néel-type with a diameter of 11-15 nm, in corresponding to the experiments. Our findings provide insights for developing room-temperature skyrmions in CNNO nanosheets for skyrmionic water-splitting performance in future energy generation and quantum computing devices.