Electron spectrometer for spin-polarized angle- and energy-resolved photoemission from ferromagnets

Abstract

An electron spectrometer allowing energy- and angle-resolved spin-polarized photoemission from ferromagnets is described. The system is designed for use with samples magnetized perpendicular to the photoelectron extraction direction (transverse magnetization geometry) and a Mott detector (100 keV) for the spin-polarization measurements. It transforms the emitting spot at the magnetic photocathode to a parallel beam which matches the size of the apertures of the Mott detector, resulting in a high efficiency. Angle selection is achieved despite initial acceleration of the photoelectrons. Energy resolution is obtained with a 90° spherical deflector connected to the Mott detector whose apertures act as the spectrometer exit slits. The performance of the setup is demonstrated by measurements with an evaporated iron film and a neon resonance lamp as light source. Sample geometries for use with the transverse magnetization configuration are discussed.