Single photon source for quantum cryptography system, has quantum point having geometric dimensions, which are formed such that transition from one conduction band energy level to another level is provided with certain energy difference

摘要

The photon source (10) has a quantum point (12) made of a semiconductor material and having geometric dimensions such that a conduction band of the semiconductor material is split up into discrete conduction band energy levels. The geometric dimensions are formed such that a transition from one of the conduction band energy levels to the other conduction band energy level is provided with certain energy difference corresponding to vacuum wavelength of more than 1.55 plus or minus 0.05 micrometers. The quantum point is made of gallium nitride or aluminum nitride.