Welcome to I05

ARPES is applied to materials with exotic electronic ground states, such as unconventional superconductors (including high Tc materials), solids exhibiting charge and spin density waves, excitonic insulators and non Fermi liquids. Due to its intrinsically high surface sensitivity and accurate mapping of momentum parallel to the surface, VUV ARPES is particularly suitable for samples with layered structures and preferential cleavage planes.

The high-resolution branch
The high resolution branch (HR-ARPES) delivers a high flux of photons in a spot size of 50 x 50 (h x v) μm². The energy resolution will allow efficient data taking at 5 – 10 meV energy resolution in the core operation range of 18 – 80 eV. Higher photon energies, up to 240 eV, can be used for band mapping. The end station will be equipped with a cryogenic six-degrees-of-freedom sample manipulator covering all emission angles in the temperature range 10 K < T < 300 K, and housed in an ultrahigh vacuum of 5x10^-11 mbar. Sample load-lock, storage and a versatile preparation chamber are used for efficient sample change, in-situ preparation and characterisation.

The nano-branch (Fresnel Zone Plate)

The nano-ARPES branch features endstation that deliveres spatailly resolved ARPES from ultra-small spot with sizes approximately 0.7 x 0.7 µm², obtained using Fresnel zone plate. Currently endstation operates in the energy range from 60 to 99 eV, providing ARPES experiment with  combined resolution of 30-50 meV. The cryo-cooling system typically can cool sample down to 24 K. Flexible adjustment of photoemission direction is possible with two-axes sample goniometer, rotation of  analyser as well as deflection mode of analyser (Scienta DA-30). Sample load-lock, preparation and characterization chambers are available for user experiment as well.

The nano-branch (Capillary Mirror, since 2020)

The nano-branch can also be used for micro-ARPES, using a capillary mirror focusing optic. This is much brighter than the zone plate (>20 times) but has a spot size of 4x4 micron FWHM. However, this enables high spectral resolution measurements at any desired photon energy in the range 20-200 eV, though the best conditions are typically 40-120 eV and typical energy resolution 20-40 meV.