Application of Geiger-Mode Avalanche Photodiodes in Dynamic Light Scattering to the Characterization of Nanoparticles

To solve the problem that it is hard to obtain high count rates for getting repeatable measurement of diameter with small, weakly scattering particles in Dynamic Light Scattering. We present a convenient alternative method for characterization of nanoparticles by using the G-APD (Geiger-Mode Avalanche Photodiodes) instead of PMT(Photomultiplier Tube). The system by G-APD is systematically tested using suspensions of latex spheres of various diameters. Comparing to measurement results by PMT, it has the advantage of high photon detection efficiency, small size, less affected by magnetic field, and less expensive.