As shown in FIG. 1A, the pump beam 101 performs a first pass 108a of the plasma 106. A first portion of the initial pass 108a of the pump beam 101 is absorbed by the plasma 106 and/or gas 107 proximate to the plasma 106. A second portion of the initial pass 108a of the beam 101 is transmitted through the partially transparent plasma 106 and is collected by mirror 110a. Mirror 110a then directs the collected illumination to a second mirror 110b, which, in turn, performs a second pass 108b of the pump beam 101 through the plasma 106. Again, a first portion of the second pass 108b of the beam 101 is absorbed by the plasma 106 and/or gas 107 proximate to the plasma 106, while a second portion of the second pass 108b of the beam 101 is transmitted through the plasma 106. This process is repeated multiple times via mirrors 110c-110d to execute passes 108c and 108d of the pump beam 101 through the plasma 106. It is noted that the scope of the present disclosure is not limited to the number or arrangement of mirrors depicted in FIG. 1A, which is provided merely for illustrative purposes. It is recognized herein that the multi-pass assembly 102 may include any number of optical elements (e.g., reflective and/or transmissive) positioned and orientated in any manner to accomplish multiple passes of pump illumination through the plasma 106.