Features:

• Direct imaging of energy resolved momentum space with Δk < 0.01 Å^-1
• Parallel energy detection of ≤ 400 slices with ΔE < 15 mev
• Start energies 0-2000 eV
• LHe-cooled hexapod stage
• Optional imaging spin filter

The METIS spectrometer is a joint development of the Johannes-Gutenberg Universität Mainz and the MPI für Mikrostrukturphysik Halle. It is produced by Surface Concept and integrated by SPECS into complete and versatile UHV systems. It consists of a sample stage, a sophisticated lens system and an analyzer section. The sample stage is a high precision 6-axes hexapod for optimal alignment of the sample towards the lens entrance. The k-microscopy column comprises multiple lens system with a high extractor voltage to analyze the full half space of photoelectrons. The analyzer section is a drift tube with a 2D-DLD detector, which can be upgraded by a spin-imaging detector.

k-Microscope Column The core of the METIS spectrometer is the lens system. With its high extractor voltages it records photoelectrons with a start energy up to 70 eV
over the full half space, simultaneously in k_x and k_y direction. This is a big advantage compared to conventional hemispherical analyzers, where only a small fraction can be measured at once. The result is a 3D dataset of Ekin, k_x and k_y, combined with a time resolution of 150 ps from the delay line detector and maximum count rates of 8 Mcps. The lens system allows for energy dispersive measurements as well as real space images. Additional apertures inside the lens system can reduce the field of view for
ARPES spectra of small areas down to μm regions or enhance the contrast for photoelectron microscopy with chemical information.

The kinetic energies of the electrons are detected in time-of-flight mode using a delayline detector (DLD). A DLD is a position (x, y) and time (t) sensitive microchannel plate area detector for imaging of single particles with temporal resolution in the picosecond range. The (x, y, t) histograms are gathered over a large number of excitation cycles of the particle generating process as the system is a single counting device. Particle images can be collected from continuous running processes with randomly incoming particle sequences without time correlation as well. The dead times of these single counting devices are typically between 6 - 20 ns, depending on the positions of subsequent hits. That enables live imaging with highest sensitivity, collecting high count rates of randomly incoming particles in the multimillion counts per second range, as well as imaging with a very high dynamic range of 10⁶. Unlike other pico-second imaging devices, delayline detectors collect all incoming particle hits continuously without any gate window duty cycles, thus (besides the device dead time limits) all hits are collected even when they represent random time positions within the excitation cycle time period. Any gate window can be configured even after acquisition, thus flexible re-ordering of data is possible without repeating measurements.