Optical and magnetic properties of silica implanted with N{sup +} and Fe{sup +}

Abstract

Silica platelets (Corning 7940) were implanted sequentially with N{sup +} at 52 keV to different doses ranging from 0 to 1.2{times}10{sup 17} ions cm{sup {minus}2} and then with Fe{sup +} at 160 keV to a dose of 6{times}l0{sup 16} ions cm{sup {minus}2}. The optical absorption decreased with increasing N{sup +} dose at photon energies ranging from 1.4 to 6.5 eV. The relative intensity, S(0{degrees}), of the ferromagnetic resonance absorption and its resonance field, H{sub s}(0{degrees}), at {theta}=0{degrees} were larger than S(90{degrees}) and H{sub s}(90{degrees}), at {theta}=0{degrees}, where {theta} is the angle between the applied magnetic field and the normal to the implanted surface. The maximum values of S(0{degrees}) and S(90{degrees}) were observed near the N/Fe atomic ratio of 0.2. At the similar atomic ratio, the differential relative intensity, S(0{degrees}){minus} S(90{degrees}), and the differential resonance field, H{sub s}(0{degrees}){minus} H{sub s}(90{degrees}), associated with the degree of magnetic interaction between the produced compounds, also showed maxima. We conclude that sequential ion-implantation of N{sup +} and Fe{sup +} into silica causes a chemical interaction to produce iron nitrides