Unveiling the dynamics of multi-peak gap nematicons: Effects of thermal response and diffractive radiation

This study investigates the effects of thermal response and diffractive radiation on multi-peak gap nematicons within a periodic potential through numerical simulations. We analyze both stationary and dynamic solutions, revealing that thermal response alone produces two-peak gap nematicons in the first bandgap, with peak separation increases in a nonlinear, parabolic manner as the thermal response coefficients increase. This separation arises from the interplay between thermal effects and refractive index changes in the nematic liquid crystal medium. When diffractive radiation is included, three-peak and four-peak gap nematicons can also be found, with an energy redistribution adjusting dynamically among peaks at different diffractive radiation shelf heights. The stability of these multi-peak structures against small perturbations is analyzed using the Bogoliubov-de Gennes equations.