Frequency-encoded linear cluster states with coherent Raman photons

TL;DR

This paper proposes a novel method using spin-flip Raman scattering in quantum dots to generate frequency-entangled photonic cluster states, overcoming limitations of incoherent emission schemes.

Contribution

It introduces a new approach employing spin-flip Raman scattering in quantum dots for practical generation of frequency-entangled cluster states.

Findings

Uses spin-flip Raman scattering for entangled photon generation

Overcomes limitations of incoherent emission schemes

Potential for practical quantum information applications

Abstract

Entangled multi-qubit states are an essential resource for quantum information and computation. Solid-state emitters can mediate interactions between subsequently emitted photons via their spin, thus offering a route towards generating entangled multi-photon states. However, existing schemes typically rely on the incoherent emission of single photons and suffer from severe practical limitations, for self-assembled quantum dots most notably the limited spin coherence time due to Overhauser magnetic field fluctuations. We here propose an alternative approach of employing spin-flip Raman scattering events of self-assembled quantum dots in Voigt geometry. We argue that weakly driven hole spins constitute a promising platform for the practical generation of frequency-entangled photonic cluster states.