Exploring 2D materials at high resolution, high sensitivity, high speed, high efficiency, and low dose

Aberration-correction, monochromation and high-acceptance angle spectrometers in state-of-the-art transmission electron microscopes make it possible to obtain information about the local atomic and electronic structure of the investigated sample with high spatial resolution and high energy resolution. The ability to detect both spectra and electron diffraction patterns with a fast direct electron detector allows every electron to be counted without any readout noise and with high efficiency, since comparatively few electrons are thrown away due to the use of apertures or lossy detection. This is particularly relevant for 2D materials, where the recorded signal is due to individual atoms. This presentation will demonstrate the acquisition of EELS data with < 6 meV energy resolution and zero-loss filtered diffraction patterns with > 15,000 frames per second on a hybrid-pixel direct detector, as well as the extraction of quantitative dielectric functions, surface plasmon dispersion curves and damping, and atomically-resolved maps of the electrostatic potential and charge density from such data.