The role of exchange interaction in nonradiative energy transfer between semiconductor quantum dots

The contribution of exchange interaction to the probability of nonradiative energy transfer between two (donor and acceptor) semiconductor quantum dots based on A$_3$B$_5$ compounds has been analyzed using the Kane model of energy-band structure. It is established that the dependence of the exchange contribution on the distance between donor and acceptor centers has a power character for nearly contact distances and acquires an exponential character when the distance increases. Numerical calculations showed that the exchange contribution is comparable with that of the dipole-quadrupole interaction of quantum dots and is one to two orders of magnitude lower than the contribution of the dipole-dipole interaction at shorter distances.