Convective instabilities in homeotropic nematic liquid crystals: Experimental results in thick layers

Experimental results are presented for Rayleigh-Bénard convection in thick horizontal layers of Homeotropic Nematic Liquid Crystal heated from below under external magnetic fields. New results are shown about the subcritical bifurcation in the oscillatory and steady convective regimes. Also, a more accurate estimation of the codimension-two point is made. The frequencies of the oscillatory solutions and other nonlinear effects are measured.