Spin-Photon Dynamics of Quantum Dots in Two-mode Cavities

TL;DR

This paper explores the interactions between quantum dots and two-mode cavities, demonstrating how they can generate entangled states or implement quantum gates with high fidelity, advancing quantum information processing.

Contribution

It introduces a two-mode Jaynes-Cummings model for quantum dots in cavities, showing new ways to generate entanglement and quantum gates depending on the quantum dot configuration.

Findings

Entanglement of electron spin and cavity states achieved

SWAP gate implementation demonstrated

Polarization entangled photon pairs generated with high fidelity

Abstract

A quantum dot interacting with two resonant cavity modes is described by a two-mode Jaynes-Cummings model. Depending on the quantum dot energy level scheme, the interaction of a singly doped quantum dot with a cavity photon generates entanglement of electron spin and cavity states or allows one to implement a SWAP gate for spin and photon states. An undoped quantum dot in the same structure generates pairs of polarization entangled photons from an initial photon product state. For realistic cavity loss rates, the fidelity of these operations is of order 80%.