On the first application of the Richardson-Lucy algorithm to resolve plasmonic resonances in EELS spectra obtained with a monochromated electron beam.

Abstract

In an article published recently in Microscopy and Microanalysis (Bellido et al., 2014), the first application of the Richardson–Lucy (RL) algorithm was claimed for the deconvolution of surface plasmon resonances in electron energy-loss spectroscopy (EELS) data obtained with a monochromated electron beam. However, we previously reported such an application (Walther et al., 2012, 2013). In this work, we studied cavity modes hybridized with surface plasmon polaritons in submicron slits in a thin Au film. Such cavity modes were reported by Carmeli et al. (2012) and strong enhancement of the cavity modes upon introduction of neighboring slits was also demonstrated (Walther et al., 2014). We performed scanning transmission electron microscopy (STEM) at 300 keV combined with EELS in a FEI Titan3 80–300 (FEI, Hillsboro, OR, USA) with excited Wien-type filter monochromator. Spectra were taken with a high-resolution Gatan Imaging Filter Tridiem 865 (Gatan) using a dispersion of 10 meV/channel. The RL algorithm was adapted to EELS as proposed by Gloter et al. (2003) in a self-written script in Digital Micrograph (Gatan, Pleasanton, CA, USA).