Effective Theory of Electron-Hole Exchange in Semiconductor Quantum Dots

Abstract

Semiconductor self-assembled quantum dots (QDs) are expected to become building blocks of novel optoelectronic devices capable of generating single photons and entangled photon pairs (EPPs) on demand. The major barrier to generation of EPPs is the so-called "bright exciton splitting" originating from the long-range electron-hole exchange interaction. A k · p effective mass theory of electron-hole exchange in semiconductor quantum dots is presented (Phys. Rev. B 81, 045311). The matrix element responsible for the "bright" exciton splitting in the effective exciton Hamiltonian is identified and analyzed. An excitonic fine structure for a model quantum dot with quasi-two-dimensional anisotropic harmonic oscillator (2DLAHO) confining potential is considered as a function of the shape and external fields.