Observation of periodic oscillations in magnetization-induced second harmonic generation at theMn∕Cointerface

Magnetization-induced optical second harmonic generation (MSHG) from exchange-biased $\mathrm{Mn}∕\mathrm{Co}$ thin films shows monolayer period oscillations at the $\mathrm{Mn}∕\mathrm{Co}$ interface as a function of Co thickness. Similar oscillations are found in the exchange bias $({H}_{E})$ and the coercivity $({H}_{C})$ in both the interface sensitive MSHG and the bulk sensitive magneto-optical Kerr effect, indicating that magnetic reversal in the Co bulk and at the $\mathrm{Mn}∕\mathrm{Co}$ interface is collinear. Assuming a linear relationship between the MSHG asymmetry and the magnetic moment, our results suggest that there is an enhancement of the interface net magnetic moment at the full monolayer regions.