Self-focusing effects in an organic photorefractive film without a biased field

Abstract

We report the observation of self-focusing effects in organic photorefractive films based on a carbazole derivative and sensitizer 2,4,7-trinitro-9-fluorenone at 632.8 nm wavelength without applying a biased field, owing to the orientationally enhanced photorefractive nonlinearity caused by photopolymerization of the carbazole derivative. The experiment was repeated in three samples with different sensitizer doping percentages and similar phenomena were observed.

Observation of holographic photovoltaic solitons in an organic glass without an external field

“…The orientational PR nonlinearity can give rise to a self-focusing effect which then balances the diffraction effects and produces PR spatial solitons [9][10][11]. We have observed the holographic focusing effect in the carbazole PR film without applying a bias field [12,13]. In this paper, we report the holographic photovoltaic soliton in the organic glass without applying an external field.…”

Recent advances in photorefractive and photoactive polymers for holographic applications

“…Self‐trapping of light has been demonstrated in organic PR glasses . Also, self‐focusing in non‐biased PR film consisting of carbazole derivative and TNF has been reported . In the latter case, the authors predicted an orientational index grating generated by the carbazole derivative with a photoreactive function and giving a coupling gain with photopolymerization …”

Control of nonlinear self-action of high-power Gaussian beams: using a nonlinear left-handed material slab

“…On the other aspect, when a high-power laser beam propagates in a conventional Kerr medium (CKM), the third-order nonlinear response of the medium will result in an intensity-dependent refractive index, which, in turn, bends the phase front of the beam. This self-action leads to a change of the energy distribution in the beam and may result in a selffocusing effect [29] and even optical damage, which seriously influences the running performance of high-power laser systems and remains an important basic scientific and engineering problem so far. Because of the special ability of nonlinear LHM in the propagation and control of light, the effect of nonlinear LHMs on nonlinear propagation in CKMs deserves systematic consideration.…”