Nanofluids representing nanometer-sized solid particles dispersed in liquids are of interest in many
fields of process and energy engineering, e.g., heat transfer, catalysis, and the design of functionalized
materials [1]. The physical, chemical, optical, and electronic properties of nanofluids are strongly driven
by the size, shape, surface potential, and concentration of the nanoparticles. For the analysis of diffusive
processes in nanofluids allowing access to, e.g., particle size and its distribution, dynamic light scattering
(DLS) is the state-of-the-art technique. It is based on the analysis of microscopic fluctuations originating
from the random thermal movement of particles in the continuous liquid phase at macroscopic
thermodynamic equilibrium. For anisotropic particles or particle aggregates, besides translational
diffusion also rotational diffusion occurs. To obtain the sum of the orientation-averaged translational
(DT) and rotational (DR) diffusivities by depolarized DLS [2], a homodyne detection scheme is usually
applied which can hardly be fulfilled in the experimental realization. Furthermore, the experiments are
restricted to limited ranges for temperature, particle concentration, and viscosity
