The Bloch beamline consists of two branchlines, and is dedicated to high resolution photoelectron spectroscopy, encompassing angle-resolved (ARPES), spin resolved (spin-ARPES) and core-level spectroscopy. Located on the 1.5 GeV storage ring, it employs an elliptically polarising undulator as a photon source. Equipped with both gas and solid state filters for minimising higher order light contamination, the Bloch beamline offers photon energies with controllable polarization spanning UV to soft X-ray (10-1000eV). This range is carefully chosen to combine extremely high momentum and energy resolution for valence-band ARPES studies with the higher energies required for detailed core level spectroscopy.

Branchline 1 has an end station dedicated to high-performance ARPES experiments, ideal for mapping energy dispersions and Fermi surfaces. The end station consists of six ultra high vacuum chambers connected by a radial-distribution chamber. Besides the main analysis chamber there are two flexible and well equipped preparation chambers (dedicated to high- and low-vapour pressure evaporation sources), a scanning tunnelling microscope, a sample storage chamber and a fast-entry load-lock. The analysis chamber is equipped with a fully motorized six-axis manipulator capable of cooling samples to below 15K, paired with a high performance deflector based DA30 hemispherical analyser from ScientaOmicron. Deflection mode measurements enable Fermi surface mapping without needing to rotate the sample, advantageous for very small or inhomogeneous samples and also for maintaining a fixed polarization geometry.

Branchline 2 will be dedicated to spin-resolved ARPES measurements. Endstation is currently in the construction phase.

Techniques

Available forTechnique description
General UsersHigh-resolution angle resolved photoelectron spectroscopy (ARPES), using deflection based analyzer or 6-axis manipulator.
General UsersLinear vertical or horizontal polarised light from EPU, with energy range 10-1000eV (peak flux and resolution 15-200eV).
General UsersOnline Scanning tunneling microscopy (STM), 50K - 300K.