Experimental Study of Spinodal Decomposition in a 1D Conserved Order Parameter System

Description

We study the zigzag instability coarsening of splay-bend walls formed in a nematic liquid crystal under external fields. The vertexes of zigzag can be considered as kinks in a one-dimensional order parameter system and the geometrical constraints associated with the necessary equal length sum of zig and zag segments impose a conserved quantity in this Cahn-Hilliard–type problem. In the late stage of coarsening, the characteristic length of the system L(t) shows a logarithmic increase in time and the dynamical scaling law holds. We then try to extract the nontrivial asymptotic scaling exponent of the two-time correlation function, defined by li(0,t)(0,t)~[L(t)/L(t)]–. The scaling exponents with respective time references, t = 32 and 64 s, after quench are found to be 2 which is larger than the value with respective time reference t = 0, predicted by numerical simulation.

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