The Effect of Frequency on the Localization of a Photon

A photon is a smearing of electromagnetic waves across a number of different wavelengths. When you do that, you introduce constructive and destructive interference in such a way that you actually localize the regions where the particle actually exists. In some regions, the electric field and magnetic field will be essentially zero, whereas in other regions, it will be much larger. But in both cases, it's, have a look at quantum field theory if you want the full answer here, because this isn't the full answer... It's only the first approximation.