• Citer

Dynamics of Sub-Diffraction-Limited Dissipative Structures in Nonlinear Resonators with Left-Handed Materials

par Kockaert, Pascal ;Tassin, Philippe;der Sande, G.;Veretennicoff, Irina;Tlidi, Mustapha
Référence Institute for Laser Physics, page (5)
Publication Publié, 2006

Publication dans des actes

• Détails
• Contenu

Résumé :

We present a nonlinear optical resonator filled with a slab of a right-handed material and of a left-handed material. We show that the diffraction coefficient of this system can be positive, negative or zero. This tuning of the diffraction can result in the formation of dissipative structures with sub-diffraction-limited wavelength. Finally, we discuss the spatiotemporal behaviour of such patterns. We have studied an externally driven optical ring cavity filled with a slab of a right-handed material and a slab of a left-handed or doubly negative material. At least one of the materials is assumed to have Kerr type nonlinearity. By constructing a mean-field model for this resonator, we show that the diffraction coefficient of this system can be made positive, negative or zero depending on the thicknesses of the slabs. We demonstrate that the dynamical behaviour of the modulational instability of the resonator is strongly affected by the sign of the diffraction coefficient. For example, while the upper branch of the bistability curve is unstable for positive (normal) diffraction, it is stable for negative diffraction. Furthermore, by tuning the diffraction coefficient very close to zero, it is possible to induce the formation of dissipative structures with sub-diffraction-limited wavelength. Finally, we study numerically the spatiotemporal behaviour of such patterns in the negative diffraction regime. We reveal that in one transverse dimension the structures are stable, but that in two dimensions a spontaneous up-switching process dominates the formation of stable periodic structures for all input intensities above the onset of modulational instability. This leads to the truncation of the homogeneous hysteresis cycle.