"Femtosecond and Attosecond Electron Microscopy with Single and Multiple Electrons"

Abstract:

All processes in materials, nanostructures and devices are on a fundamental level defined by electronic and atomic motion from initial to final conformations. Atoms realign in femtoseconds and electron densities respond in attoseconds when interacting with laser light. Our approach for a direct, real-space visualization is pump-probe electron diffraction and microscopy with single-electron wavepackets under the control of laser light.

Terahertz waves are ideal to obtain isolated electron pulses while modulation with the optical cycles of continuous laser light provides a train of electron pulses with attosecond shapes. Using these concepts, we can visualize atomic motions and electron dynamics in space and time. We will report selected results on magnetic materials, electronic circuitry, and light-wave propagation around metamaterials. We will also report latest results on utilizing pulses with more than one electron to understand the quantum-mechanical basics of electron-electron interaction and scattering with materials.