Strain-Induced One-Dimensional Magnetic Stripe in Metallic Monolayer H-NbSe₂

Lattice distortion of materials has a profound impact on their electronic and magnetic properties, which can generate local magnetic states in intrinsically non-magnetic systems. Here we report on the realization of a one-dimensional (1D) magnetic stripe in monolayer H-NbSe₂ sustained by strain along the terraces of the graphene/SiC substrates. The strength of this tensile strain is widely tunable by the height-to-width ratio of the terraces. Increasing the tensile strength leads to the shifts and splitting of the Nb 4d bands crossing the Fermi energy, generating spin polarization in a 1D magnetic stripe along the terrace. Simultaneously, the charge-densitywave signature of strained H-NbSe₂ is significantly suppressed. Such a magnetic stripe can be locally quenched by an individual Se-atom defect via the defect-induced Jahn-Teller distortion and charge density redistribution. These findings provide a different route to achieving and manipulating 1D magnetism in otherwise non-magnetic systems, offering a new way for spintronic devices.