All-Optical Three-Dimensional Electron Momentum Imaging

We report a new implementation of three-dimensional (3D) momentum imaging for electrons, employing two-dimensional (2D) detector and silicon photomultiplier tube (siPMT). To achieve the necessary time resolution 3D electron imaging, poly(p-phenylene)-dye-based fast scintillator (Exalite 404) was used in instead conventional phosphors. The system demonstrated an time-of-flight comparable with that electrical MCP pick-off (tens picoseconds), while achieving unprecedented dead reduction (?0.48 ns) when detecting two electrons.