Heavy ion irradiation induced structural and magnetic modifications in Co/Alq3 bilayer.

This article reports on the Ar+ ion irradiation induced modifications of Co/Alq 3 /Si-substrate bilayer thin film. Irradiation was carried out with 10 keV Ar+ ions at a fluence of 1 × 1016 ions/cm2. To study structural and magnetic modifications, x-ray reflectivity (XRR) and magneto-optical Kerr effect (MOKE) techniques, respectively have been utilized. XRR analysis reveals a significant reduction of electron density of the Co layer and enhancement of intermixing of Co and Alq 3 at the Co/Alq 3 interface after ion irradiation. MOKE measurements affirm that saturation magnetization reduces by a factor of about 3 due to irradiation without any detectable changes in the coercivity. XRR analysis and Monte Carlo simulation demonstrate the ion irradiation induced defects formation due to Ar implantation and enhancement of interface mixing between Co and Alq 3 is the main cause of the reduction in saturation magnetization. [ABSTRACT FROM AUTHOR]