Spatiotemporal Defects in Weakly Nonlinear Traveling-Wave Convection

Convection in binary fluid mixtures begins with an oscillatory instability to a state of traveling waves (TW) for negative values of the separation ratio psi. Just above onset, these linear TW evolve into nonlinear states which, for sufficiently psi (here, psi = -0.021) exhibit many of the characteristics of linear TW, but which are found, in a rectangular container, to 'slosh' back and forth across the cell on long time scales.