Spreading and M 2-factor of elegant Hermite–Gaussian beams through non-Kolmogorov turbulence

Using a non-Kolmogorov power spectrum, analytical expressions for the beam width, angular spread and M 2-factor of elegant Hermite–Gaussian (EHG) beams through non-Kolmogorov turbulence are derived. It is shown that the beam-width spreading, angular spread and M 2-factor of EHG beams through non-Kolmogorov turbulence depend on the non-Kolmogorov turbulence, i.e. on the generalised exponent parameter, , the inner scale, l 0, and the outer scale, L 0, at a sufficient propagation distance. They increase with increasing outer scale for 3.6< <4, and with decreasing inner scale. Only at a shorter propagation distance is the effect of turbulence on the beam-width spreading and M 2-factor negligible. The results are interpreted physically.