Frequency-controllable electric field distribution in colloidal crystals

The study of electric field distributions in graded systems is important due to various applications. We establish an analytical method based on the Maxwell equations, to investigate electric field distributions in graded multilayered colloidal crystals. This analytical method agrees very well with an existing numerical method. It convincingly explains and confirms the fact that the peak of electric field distributions is controllable to appear in a specific layer, by tuning the angular frequency of an incident light. Also, this method offers a more convenient way to the understanding of electric field distributions in colloidal crystals.