Demonstration of single-shot picosecond time-resolved MeV electron imaging using a compact permanent magnet quadrupole based lens

TL;DR

This paper demonstrates a compact, high-gradient permanent magnet quadrupole lens capable of single-shot, picosecond time-resolved MeV electron imaging of micron-scale features, advancing electron microscopy capabilities.

Contribution

It introduces a novel compact permanent magnet quadrupole lens system for single-shot, picosecond electron imaging with high magnification, enabling new applications in time-resolved electron microscopy.

Findings

Achieved over 30x magnification in a single shot.

Used a 1.3 cm focal length lens with 600 T/m gradient.

Demonstrated imaging of micron-scale features with high brightness electron beams.

Abstract

We present the results of an experiment where a short focal length (~ 1.3 cm) permanent magnet electron lens is used to image micron-size features of a metal sample in a single shot, using an ultra- high brightness ps-long 4 MeV electron beam from a radiofrequency photoinjector. Magnifcation ratios in excess of 30x were obtained using a triplet of compact, small gap (3.5 mm), Halbach-style permanent magnet quadrupoles with nearly 600 T/m field gradients. These results pave the way to- wards single shot time-resolved electron microscopy and open new opportunities in the applications of high brightness electron beams.