Chip-based electrostatic beam splitting of guided kiloelectron volt electrons

We present a beam splitter for guided electrons using an electrostatic guiding potential created above the surface of two opposing planar microstructured printed circuit boards. The electric fields acting on the electrons result in a ponderomotive potential. We show that we can smoothly transition the ponderomotive potential from a single-well into a double-well, which leads to the splitting of the electron beam. Efficient beam splitting is observed over a large range of kinetic energies starting at 200 eV up to 1700 eV. We discuss future work needed to reach adiabatic beam splitting for quantum state-selective electron optics. This will pave the way for an electron interferometer on a chip and, therefore, result in until now not possible elements for electron optics and microscopy.