Speaker
Description
Scanning electron microscopy (SEM) is widely used for rapid, nanoscale morphological imaging of bulk specimens. This success has also shaped its common role as a complementary characterization tool, rather than as a platform for spectroscopic and dynamical measurements. Recent developments in energy-selective electron detection, secondary-electron energy spectroscopy [1], reflected-electron energy-loss spectroscopy [2], and pump–probe SEM [3] are beginning to change this picture by adding spectral and temporal contrast to the native surface sensitivity and large-sample compatibility of SEM.
Here, we discuss emerging opportunities for ultrafast hyperspectral SEM as a tabletop approach to map electronic structure, collective excitations, and photoinduced dynamics in nanostructured materials and devices. We focus on strategies that combine energy, time, and, where accessible, momentum filtering in a multidimensional SEM workflow. In particular, we consider the integration of secondary-electron emission spectroscopy and reflected-electron energy-loss spectroscopy with optical excitation, aiming to connect surface electronic structure, dielectric response, and transient charge or plasmonic phenomena under realistic sample geometries.
Such an approach could provide a bridge between conventional SEM imaging and the spectroscopic capabilities more commonly associated with transmission electron microscopy, ultrafast electron microscopy, photoemission, or large-scale facilities. By enabling nanoscale, surface-sensitive, and potentially operando measurements on bulk specimens, ultrafast hyperspectral SEM may expand access to dynamical electron–photon interaction studies in quantum materials, nanophotonics, optoelectronic devices, and functional interfaces.
[1] W. Han, M. Zheng, A. Banerjee, Y.Z. Luo, L. Shen, A. Khursheed, Quantitative material analysis using secondary electron energy spectromicroscopy, Scientific Reports 10(1), 22144 (2020) - 202010.1038/s41598-020-78973-0
[2] W.S.M. Werner, K. Glantschnig, C. Ambrosch-Draxl, Optical Constants and Inelastic Electron-Scattering Data for 17 Elemental Metals, Journal of Physical and Chemical Reference Data 38(4), 1013–92 (2009) - 200910.1063/1.3243762
[3] M. Zani, V. Sala, G. Irde, S.M. Pietralunga, C. Manzoni, G. Cerullo, G. Lanzani, A. Tagliaferri, Charge dynamics in aluminum oxide thin film studied by ultrafast scanning electron microscopy, Ultramicroscopy 187, 93–7 (2018) - 10.1016/j.ultramic.2018.01.010