An ellipsoidal mirror display analyzer system for electron energy and angular measurements

Abstract

A new electron imaging analyzer is described which consists of a retarding field ellipsoidal mirror low pass energy filter, a retarding field spherical grid high pass filter, and an area detector which consists of a CEMA multiplier, phosphor screen, and data acquisition system. This analyzer system energy analyzes and directly displays and measures all angular (momentum) directions within a ∼85° cone (∼1.8 sr). Angular resolutions of δθ {reversed tilde equals} 2° and energy resolutions ΔE {less-than or approximate} 100 meV are obtained for angle-resolved photoemission measurements using synchrotron radiation. It has a very high throughput when used as an angle-integrated analyzer, with a resolution ΔE {less-than or approximate} 0.2 eV which can be achieved for a wide range of energies through the use of a spherical pre-retard lens. Descriptions are given of the ellipsoidal mirror design, system design, and system performance. © 1980.