  We study diffusion of heat in an aqueous suspension of disc shaped
nanoparticles of Laponite, which has finite elasticity and paste-like
consistency, by using the Mach-Zehnder interferometer. We estimate the thermal
diffusivity of the suspension by comparing the experimentally obtained
temperature distribution to that with analytical solution. We observe that
despite highly constrained Brownian diffusivity of particles owing to its soft
glassy nature, suspensions at very small concentrations of Laponite
demonstrates significant enhancement in thermal diffusivity. We correlate the
observed enhancement with the possible microstructures of the Laponite
suspension.
