High speed and high efficient all optical switch using exciton-polaritons in GaAs thin films

Summary form only given. We have been investigated optical properties of precisely size-controlled GaAs thin films, where exciton motion is quantized and non-local interaction between excitons and photons should be considered. We observed an enhanced third-order nonlinear optical response for a 110 nm-thick GaAs film using degenerate four-wave mixing. The observed nonlinear response was 25 times larger than that of a 1 /spl mu/m-thick film. This result agrees with a theoretical proposal of enhanced nonlinear optical responses of exciton-polaritons in a thin film with a particular thickness. In this paper, we demonstrate, for the first time, optical switching using nonlinear optical responses of exciton-polaritons in a GaAs thin film.