Towards Tripartite Hybrid Entanglement in Quantum Dot Molecules

TL;DR

This paper demonstrates the generation of tripartite hybrid entanglement in quantum dot molecules, advancing scalable quantum computing and communication by exploiting correlated excitonic complexes and multi-level ground states.

Contribution

It introduces a method to generate tripartite hybrid entanglement using strongly correlated quantum dot molecules with controlled carrier interactions.

Findings

Successfully created tripartite hybrid entanglement in quantum dot molecules.

Identified conditions for maintaining spectral components suitable for entanglement.

Analyzed spectral broadening effects on photon indistinguishability.

Abstract

Establishing the hybrid entanglement among a growing number of matter and photonic quantum bits is necessary for the scalable quantum computation and long distance quantum communication. Here we demonstrate that charged excitonic complexes forming in strongly correlated quantum dot molecules are able to generate tripartite hybrid entanglement under proper carrier quantization. The mixed orbitals of the molecule construct multilevel ground states with sub-meV hole tunneling energy and relatively large electron hybridization energy. We show that appropriate size and interdot spacing maintains the electron particle weakly localized, opening extra recombination channels by correlating ground-state excitons. This allows for creation of higher order entangled states. Nontrivial hole tunneling energy, renormalized by the multi-particle interactions, facilitates realizing the energy coincidence among only certain components of the molecule optical spectrum. This translates to the emergence of favorable spectral components in a multi-body excitonic complex which sustain principal oscillator strengths throughout the electric-field-induced hole tunneling process. We particularly analyse whether the level broadening of favorable spin configurations could be manipulated to eliminate the distinguishability of photons.