Molybdenum Laser Mirrors for Diagnostic Systems of TRT Tokamak

The possibility of using MChVP molybdenum as a material for in-vacuum laser mirrors in the TRT tokamak as an alternative to single-crystal molybdenum mirrors is considered in this work. The dynamics of the mirror surface modification under the impact of pulsed laser radiation is demonstrated. The dependence of the laser breakdown threshold on the number of laser pulses is studied. Comparison of the experimental results with the model of laser-induced fatigue failure for molybdenum mirrors showed that the deviation from the model is due to the selective erosion of the surface in the laser spot stemming from the presence of grains with different orientations.