We compute electromagnetic fields created by a relativistic charged spin-half particle in empty space at distances comparable to the particle Compton wavelength. The particle is described as a wave packet evolving according to the Dirac equation. It produces the electromagnetic field that is essentially different from the Coulomb field due to the quantum diffusion effect.This is a manuscript of an article published as Peroutka, Balthazar, and Kirill Tuchin. "Quantum diffusion of electromagnetic fields of ultrarelativistic spin-half particles." Nuclear Physics A 966 (2017): 64-72. DOI: 10.1016/j.nuclphysa.2017.05.104. Posted with permission.</p
