Study of Vibrational Modes of MeV Ni Ion Implanted MgO Crystal

The control over various vacancy and substitutional defects by ion implantation provides many interesting properties for the modulation of materials. In this report, we studied the effect of defects and anionic vacancies produced by MeV Ni ion implanted MgO on different vibrational active modes in single crystal MgO. The breathing mode of D bands is observed for most of the Raman peaks, and simultaneously, the overlapping of D and G bands is confirmed from Raman spectra. The Fourier Transform Infrared spectra identified the stretching and bending vibrations of Mg, O, and Ni atoms and compared them with pristine. The presence of atmospheric constituents and their role in affecting the vibrational modes are well justified. The phonon band and density of states calculation in the framework of density functional theory confirms the presence of T1u and T2u Raman active mode that arises due to vibration from different vacancy and substitutional defect associated in MgO structures, agrees well with experimental results. The tunable anionic vacancies produced in MgO by ion implantation can be beneficial to form the filament in valance charge memory-based RRAM. [Display omitted] •One MeV Ni ion implantation in crystalline MgO produces a lot of vacancy and substitutional defects.•Defects play a role in inducing vibrational modes in MgO.•The density functional theory (DFT) helps to find the origin of the induced modes.•The Fourier Transform Infrared spectra are also studied and understood to identify the stretching and bending vibrations.