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 quasi-periodic elliptically polarising undulator (q-epu) as a photon source. Equipped with gas filters, solid state filters and q-epu for minimising higher order light contamination, the BLOCH beamline offers photon energies with controllable polarization spanning UV to soft X-ray (10-1000eV). The beamline is optimised for lower energies and is capable of 1meV resolution upto 100 eV.
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 20K, paired with a high performance deflector based DA30 hemispherical analyser from SCIENTA-OMICRON. Deflection mode measurements enable Fermi surface mapping without needing to rotate the sample which is 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 design phase.
Research applications at this beamline cover a range of important topics in material science, including new materials, various class oftopological materials, surface alloys, correlated systems, organic molecular layers, magnetic semiconductors, superconductors etc.