Modifications of the magnetic properties of $\mathrm{Co}/\mathrm{Mo}/\mathrm{Co}$ films activated by irradiation with 30-keV Ar and 17-keV Ne ion beams are investigated and compared with the influence of 35-keV Ga ions. This system is magnetized in the sample plane and exhibits a twofold anisotropy. The interlayer coupling of magnetization in as-deposited structures is parallel except for the Mo spacer thickness range between 0.5 and 1.0 nm, where the magnetization of the Co layers is antiparallel oriented. The coupling changes and gradually reduced strength of the ferromagnetic properties are compared for all ion types and discussed as a function of the Mo spacer thickness and the ion fluence. The structural evolution of the studied films with increasing fluence determined from tridyn simulations is discussed in relation to the observed magnetic changes. We also propose various types of magnonic crystals that can be fabricated by exploiting the results presented in this work.

• Received 12 May 2017
• Revised 13 October 2017

DOI:https://doi.org/10.1103/PhysRevApplied.9.014029