Sub-ps pump and probe photoemission from polycrystalline molybdenum

Pump and probe electron photoemission, induced by 150 fs-790 nm laser pulses on polycrystalline molybdenum, is used to investigate the non-linear photoemissive regime. The analysis of these experimental data evidences third and fourth order thermally assisted currents that contribute to the electron yield. In addition, partial yield measurements at very low pulse intensities confirm the above analysis, evidencing a change in the logarithmic slope as predicted by the theory.