Optimizing the magnetic contrast in the optical second‐harmonic response of capped magnetic nanostructures grown on vicinal surfaces

Abstract

AbstractMeasuring the magnetic response from buried interfaces using magnetic second harmonic generation (MSHG) is difficult due to the general complexity of the response and the often poor signal‐to‐noise ratio (SNR). Low dimensional nanostructures grown by self‐assembly at aligned atomic steps, which typically exhibit only 1m symmetry, are particularly challenging. Near‐normal incidence SHG simplifies the crystallographic nonlinear response from such low symmetry systems by effectively excluding z‐dependent tensor components. A phenomenology is developed to show that, for 1m vicinal systems, careful choices of input and output polarization and experimental geometry can produce enhanced magnetic contrast and thus allow magnetic hysteresis loops with improved SNR to be extracted. An example of the application of this new MSHG approach to Fe monolayers grown on vicinal W(110), capped by 16 nm of Au, is discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)