A source of photons resulting from a recombination of localized excitons, including a semiconductor layer having a central portion surrounded with heavily-doped regions; above said central portion, a layer portion containing elements capable of being activated by excitons, coated with a first metallization; and under the semiconductor layer, a second metallization of greater extension than the first metallization. The distance between the first and second metallizations is on the order of from 10 to 60 nm; and the lateral extension of the first metallization is on the order of from λ0/10*ne to λ0/2*ne, where λ0 is the wavelength in vacuum of the emitted light and ne is the effective refractive index of the mode formed in the cavity created by the two metallizations.