Two-dimensional optical lattices in aCO2laser

Dynamics of Traveling Waves in the Transverse Section of a Laser

“…In nonlinear optics [1], such studies have been motivated by the goal of developing a general understanding to describe the emergence of periodic [2,3] and quasiperiodic patterns [4], vortices [5,6] or spatial solitons [7] using various passive nonlinear optical systems as well as gas [8][9][10][11] and semiconductor lasers [3,12 -14]. The analysis of the transverse structure of the light emitted by large aperture semiconductor lasers is extremely interesting due to the strong phase-amplitude coupling of the active material, as parametrized by the factor [15].…”

Probabilistic approach to pattern selection

“…This happens in lasers [21][22][23] as well as in photorefractive crystals [18][19][20]. For Fresnel numbers F > 15, the arising spatial structures are very different from those associated with the empty-cavity modes.…”

“…Contrary to the regime of small F , when the regular spatial structures are prescribed by the geometry and boundary conditions imposing their symmetry constraints, the turbulent optical filamentation is strictly self-organized, with its organization emerging from intrinsic properties of the medium [20,24]. This kind of optical turbulence has been observed in both photorefractive crystals [18][19][20] and lasers [21][22][23][25][26][27][28][29][30]. Especially accurate and thorough experimental studies for CO 2 and Dye lasers have been accomplished in Refs.…”

“…Around F ≈ 10 there occurs a principal change of properties, from the existence of regular structures to a turbulent-type state [21][22][23], with the intermittent behaviour in the region 5 < F < 15. This happens in lasers [21][22][23] as well as in photorefractive crystals [18][19][20].…”

“…In the typical experiments [21][22][23][25][26][27][28][29][30][31][32][33][34][35] observing the turbulent photon filamentation, the excitation was achieved by means of the quasistationary nonresonant pumping. Such a pumping can be treated as a quasistationary process if its duration is much longer than the characteristic time 2π/ω of fast oscillations, which is always the case.…”