CASCADE OF STRUCTURES IN THE THERMOCONVECTION OF A NEMATIC IN THE DIRECTOR-DOMINATED REGIME

We report on the first experimental study of the nonlinear evolution o f thermoconvection in a planar nematic liquid crystal, in extended geo metry and at zero or weak stabilizing magnetic field. As the control p arameter is adiabatically increased, we show that the system undergoes a series of bifurcations between stationary convective structures. We stress that this scenario is generic in the convection of a nematic i n a regime where the director nonlinear couplings dominate, independen tly of the basic convective mechanism.