Magnetic field paralleliser for 2π electron-spectrometer and electron-image magnifier

TLDR

The instrument employs a diverging magnetic field ranging from 1 T to 10⁻³ T to parallelise electrons of 0–3 eV produced by multiphoton ionisation. The device converts electrons emitted over 2π steradians into a 2° half‑angle beam, achieves 15 meV energy resolution with time‑of‑flight, functions as an electron‑image magnifier with a few‑micron spatial resolution, and is supported by detailed theoretical and computational analyses.

Abstract

An electron-optical device has been constructed in which electrons originally emitted over 2 pi steradians from a region of small volume are formed into a beam of half-angle 2 degrees . The instrument makes use of a magnetic field that diverges from 1 to 10-3 Tesla. The energies of the electrons parallelised in this way have been measured with a time-of-flight technique, giving energy resolutions as low as 15 meV. Electrons of energy 0-3 eV, formed in multiphoton ionisation, were used for these tests. The device can also act as an electron-image magnifier, giving a spatial resolution of a few mu m in the source plane. Detailed theoretical and computational results on the properties of the new apparatus are given.