Long-Term Stable Structures Formed by Ion-Beam Modification of Silver Film for SERS Applications

Ensembles of silver nanoparticles (NPs) with size ~45 nm formed from the silver film using an ion beam modification are studied. The optical spectroscopy demonstrated that the fabricated ensembles of silver NPs keep stable their plasmonic properties in an ambient atmosphere for at least 39 days due to their monocrystalline nature. We use the scanning Raman microscope to map the SERS from Crystal Violet homogeneously adsorbed on these ensembles. It was found that the manufactured ensembles have a strong amplification factor, and this factor is preserved for these ensembles even after more than one month of storage in the surrounding atmosphere. Hereby, by ion beam modification of silver film, it is possible to fabricate the NPs with stable plasmonic properties and form nanostructured surfaces to be applied in sensor technologies and SERS.

Synergistic Effects Under Ion-Beam Modification of Metals

The combined effect of ion and laser beams on physical and mechanical properties of metal and alloy surfaces has been studied. The technique of determining the main parameters of polyenergetic ion implantation using a vacuum-arc ion source is proposed and evaluated. It is found that treatment with titanium ions and the subsequent laser thermal hardening increase microhardness of steel 45 and U8 up to 6 times.

ION BEAM MODIFICATION OF MAGNETIC TUNNEL JUNCTIONS

In this work, the effect of bombardment with high-energy ions on the parameters of magnetic tunnel junctions based on CoFeB / MgO, such as magnetic anisotropy, magnetoresistance, and the damping coefficient of magnetization precession, is investigated. The modeling of the ferromagnetic resonance spectra was carried out within the framework of the Smit-Beljers and Landau-Lifshitz-Gilbert formalisms. The ion fluence limit is established, below which a controlled modulation of the magnetic anisotropy is achieved while maintaining a high tunneling magnetoresistance and stable magnetic configuration of the transition