Electric field distribution in polymer light-emitting electrochemical cells

We use electroabsorption spectroscopy and modeling studies to probe the ele ctric field in light-emitting electrochemical cells. At room temperature an d constant applied bias, the steady-state internal field is zero For a rang e of biases. However, when the ions are frozen in place by cooling under st eady bias, and the bias is subsequently changed, the profile of the electri c potential resembles a typical p-n junction.