Manipulation of ordered layered structures by interface-assisted ion-beam mixing in immiscible Ag-Co and Ag-Ni systems

Artificial ordered layered structures were grown in the nanosized Ag-Co and Ag-Ni multilayered films upon ion irradiation and were both identified to consist of two overlapping fcc lattices, corresponding to new magnetic states of ferromagnetic metals Co and Ni. Surprisingly, in the newly formed structures, the average magnetic moment per Co atom was found to be 2. 84₁, much larger than ever reported before, while the average magnetic moment per Ni atom decreased to 1/3 of its equilibrium value. The driving force for growing the ordered layered structures was from a dynamic atomic collision triggered by ion irradiation together with interfacial free energy, which was properly designed to elevate the initial state of the multilayered films up to nearby the respective highly energetic nonequilibrium levels in the immiscible Ag-Co and Ag-Ni systems.