Long-range radiative interaction between semiconductor quantum dots

Abstract

We develop a Maxwell-Schr\"odinger formalism in order to describe the radiative interaction mechanism between semiconductor quantum dots. We solve the Maxwell equations for the electromagnetic field coupled to the polarization field of a quantum dot ensemble through a linear nonlocal susceptibility and compute the polariton resonances of the system. The radiative coupling, mediated by both radiative and surface photon modes, causes the emergence of collective modes whose lifetimes are longer or shorter compared to the ones of noninteracting dots. The magnitude of the coupling and the collective-mode energies depend on the detuning and on the mutual quantum dot distance. The spatial range of this coupling mechanism is of the order of the wavelength. This coupling should therefore be accounted for when considering quantum dots as building blocks of integrated systems for quantum information processing.