We study the influence of field diffusion on the spatial localized structures (cavity solitons) recently predicted in bidirectional lasers. We find twofold positive role of the diffusion: 1) it increases the stability range of the individual (isolate
d) solitons; 2) it reduces the long-range interaction between the cavity solitons. Latter allows the independent manipulation (writing and erasing) of individual cavity solitons.
In this paper we have considered the problem of parametric sound generation in an acoustic resonator flled with a fluid, taking explicitely into account the influence of the nonlinearly generated second harmonic. A simple model is presented, and its
stationary solutions obtained. The main feature of these solutions is the appearance of bistable states of the fundamental field resulting from the coupling to the second harmonic. An experimental setup was designed to check the predictions of the theory. The results are consistent with the predicted values for the mode amplitudes and parametric thresholds. At higher driving values a self-modulation of the amplitudes is observed. We identify this phenomenon with a secondary instability previously reported in the frame of the theoretical model.
We derive the model equations describing the thermoacoustic resonator, that is, an acoustical resonator containing a viscous medium inside. Previous studies on this system have addressed this sytem in the frame of the plane-wave approximation, we ext
end the previous model to by considering spatial effects in a large aperture resonator. This model exhibits pattern formation and localized structures scenario.
We show theoretically that a broad area bidirectional laser with slightly different cavity losses for the two counterpropagating fields sustains cavity solitons (CSs). These structures are complementary, i.e., there is a bright (dark) CS in the field
with more (less) losses. Interestingly, the CSs can be written/erased by injecting suitable pulses in any of the two counterpropagating fields.
