An experimental setup for time- and angle-resolved photoemission spectroscopy using a femtosecond high harmonic light source and a two-dimensional electron analyzer for parallel energy and momentum detection is presented. A selection of the 27th harmonic from the harmonic spectrum of the light source is achieved with a multilayer double mirror monochromator. The extinction efficiency of the monochromator in selecting this harmonic is shown to be better than 7:1, while the transmitted bandwidth of the selected harmonic is capable of supporting temporal pulse widths as short as . The recorded photoelectron spectrum from a Cu(111) surface demonstrates an angular resolution of better than 0.6° ( at ). Used in a pump-probe configuration, the described experimental setup represents a powerful experimental tool for studying the femtosecond dynamics of ultrafast surface processes in real time.
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The HHG light source delivers photons/pulse. The aluminium filter reduces the flux by a factor of 10. The double mirror monochromator selects the 27th harmonic and additionally reduces the flux by about a factor of 5. The overall transmission of the 27th harmonic by the two mirrors is 4%. Residual intensity is therefore photons/pulse.