Figure 1

Experimental setup. The Nd:YAG (neodymium doped yttrium aluminum garnet) crystal is pumped by nine beams from an argon laser. The intensities of the nine lasers are recorded simultaneously by the charge coupled device camera.Reuse & Permissions

Figure 2

(a) Experimentally measured ensemble-averaged cross-correlation coefficient $⟨{\Gamma }_i⟩$ as a function of the relative group separation $D_i/d_{\mathrm{n}\mathrm{.}\mathrm{n}\mathrm{.}}$ in the case of a nine laser array. The three sets of data are related to slightly different tilts of the lens array. (b) Numerically calculated $⟨{\Gamma }_i⟩$ versus $D_i/d_{\mathrm{n}\mathrm{.}\mathrm{n}\mathrm{.}}$ in the case of a nine laser array. The angular detuning frequencies are chosen from a normal random distribution with mean zero and standard deviation of $\Delta {\omega }_c=2\times {10}^5{\mathrm{s}}^{-1}$ (squares), $3\times {10}^5{\mathrm{s}}^{-1}$ (circles), and $2.5\times 2\pi \times {10}^5{\mathrm{s}}^{-1}$ (crosses). They are generated by the $randn$ MATLAB function. The state of the generator is set to 1. The corresponding values of $d_{\mathrm{n}\mathrm{.}\mathrm{n}\mathrm{.}}$ are 545, 535, and $485\mu \mathrm{m}$, respectively.Reuse & Permissions

Figure 3

Numerically calculated ensemble-averaged cross-correlation coefficient $⟨{\Gamma }_i⟩$ as a function of the relative group separation $D_i/d_{\mathrm{n}\mathrm{.}\mathrm{n}\mathrm{.}}$ in the case of a 400 laser array for five different values of the nearest-neighbor separation $d_{\mathrm{n}\mathrm{.}\mathrm{n}\mathrm{.}}$, namely, $500\mu \mathrm{m}$ (open triangles), $460\mu \mathrm{m}$ (filled triangles), $440\mu \mathrm{m}$ (crosses), $430\mu \mathrm{m}$ (squares), and $422\mu \mathrm{m}$ (stars). The distribution of the angular detuning frequencies is generated in the same way as in Fig. 2b but with a standard deviation $\Delta {\omega }_c=2.5\times 2\pi \times {10}^5{\mathrm{s}}^{-1}$. The first ten data points of each distribution have been approximated with the power law $⟨{\Gamma }_i⟩=c-b(D_i/d_{\mathrm{n}\mathrm{.}\mathrm{n}\mathrm{.}}{)}^a$. The corresponding values of the exponent $a$ are given in the figure.Reuse & Permissions

Figure 4

Numerically calculated exponent $a$ as a function of the coupling strength and the distance between the nearest-neighbor lasers.Reuse & Permissions