Spatially resolved quantitative magnetic order measurement in spinel CuCr2S4 nanocrystals

We have utilized spatially resolved high resolution electron energy loss spectroscopy to quantify the relative percentage of ferromagnetic order in the core and the surface regions of CuCr2S4 nanoparticles with nanocube and nanocluster morphology. The organic capping layer is found to play a significant role in restoring magnetic order at the surface. The technique is based on recording the fine features of the Cr L-3 absorption edge and matching them with the theoretical spectra. The nanoscale probing technique we have developed is quite versatile and can be extended to understand magnetic ordering in a number of nanodimensional magnetic materials. (C) 2015 AIP Publishing LLC.