Nanosecond photothermal dynamics in colloidal suspension

Publisher Website
Google Scholar
Abstract
Thermal diffusion from a single colloidal sphere suspended in an aqueous medium that is heated by a laser pulse is examined. The temperature field as a function of position and time arising from the cooling of a hot colloidal sphere suspended in an infinitely extended aqueous medium is obtained by solving the heat conduction equation with initial, asymptotic, boundary conditions using a Laplace transform technique. A polymethylmethacrylate sphere of 83 nm diameter is calculated to cool in water within 7 ns. The cooling time is found to decrease quadratically with the particle diameter. We discuss the use of arrays of dyed polymethylmethacrylate spheres suspended in a refractive‐index‐matched aqueous medium as a fast (ns) optical switching device which acts as an optical monostable.

This publication has 14 references indexed in Scilit: