Simulation of the impact of misalignment on the propagation of the beam inside a thin-disk multipass amplifier

We present a simulative investigation of how the beam propagates inside a thin-disk multipass amplifier (TDMPA) based on quasi-collimated propagation when different optical elements of the TDMPA experience misalignment. A ray-tracing tool was specifically developed to investigate how misaligned elements displace the beam's position on the subsequent elements in the TDMPA. It is shown that this displacement varies periodically along the beam path. Furthermore, it is explained how different optical elements influence the amplitude, period, phase, and even amplification or damping of this oscillation, allowing for future improvements in the design of TDMPAs.