Fig. 4. Transmission electron microscopy and diffraction with terahertz-compressed electron pulses.

(A) Microscope images at a magnification of 200,000 of gold nanoparticles without (left) and with (right) terahertz compression. (B) Line cuts at the dotted lines for uncompressed (orange) and compressed 19-fs electron pulses (green). Feature sizes of 3 nm can be resolved in both cases. (C) Diffraction pattern of crystalline silicon recorded without (left) and with (right) terahertz compression. (D) Measured beam sizes of the uncompressed (orange) and compressed (green) electron pulses as a function of the microscope objective lens defocus. The focus shifts by 20 μm.