Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1901.03631 · Physical Review Letters

Generating Maximal Entanglement between Spectrally Distinct Solid-State Emitters

David L. Hurst, Kristoffer B. Joanesarson, Jake Iles-Smith, Jesper Mørk, Pieter Kok

Published Jul 9, 2019• 13 citations
arXivHTMLPDF

Abstract

We show how to create maximal entanglement between spectrally distinct solid-state emitters embedded in a waveguide interferometer. By revealing the rich underlying structure of multiphoton scattering in emitters, we show that a two-photon input state can generate deterministic maximal entanglement even for emitters with significantly different transition energies and linewidths. The optimal frequency of the input is determined by two competing processes: which-path erasure and interaction strength. We find that smaller spectral overlap can be overcome with higher photon numbers, and quasimonochromatic photons are optimal for entanglement generation. Our work provides a new methodology for solid-state entanglement generation, where the requirement for perfectly matched emitters can be relaxed in favor of optical state optimization.

DOI
10.1103/physrevlett.123.023603

Related papers

Cumulative generation of maximal entanglement between spectrally distinct qubits using squeezed light

Elena Callus, Pieter Kok

We demonstrate how to create maximal entanglement between two qubits that are encoded in two spectrally distinct solid-state quantum emitters embedded in a waveguide interferometer. The optical probe is provided by readily accessible squeezed light, generated by parametric down-conversion. By continuously illuminating the emitters, the photon scattering and incremental path-erasure builds up entanglement. Our method does not require perfectly identical emitters, and accommodates spectral variations due to the fabrication process. Furthermore, for some linewidth and energy ratios, the entanglement buildup can be significantly faster than for more similar emitters. It is also robust enough to create entanglement with a concurrence above 99% in the event of scattering losses and detector inefficiencies and can form the basis for practical entangled networks.

arXiv:2102.12341•Physical Review A•Nov 9, 2021•7 citations

High-fidelity entanglement of two spectrally-distinct solid state emitters

Daniel R. E. Hodgson, Pieter Kok

Solid state quantum emitters with electronic spin properties can be entangled using optical interferometric which-path erasure techniques that rely on identical frequencies and linewidths of the emitters. This promises a powerful, fast and scalable platform for quantum technologies. Using current protocols, a pair of emitters embedded in a waveguide interferometer can be deterministically prepared in a maximally entangled state. However, the amount of entanglement diminishes rapidly with increasing separation of the emission lines and variations in the linewidths of the emitters. Solid state emitters such as quantum dots are subject to intrinsic variations in the fabrication process. Therefore, manufacturing the required number of identical emitters on a chip is not scalable. In this Letter, we present a method that uses readily available pairs of entangled photons to entangle solid state emitters with large transition frequency separations and linewidth variations, circumventing the need to fabricate optically identical emitters. We demonstrate a concurrence of C = 0.95 for typical quantum dots using narrowband photon inputs.

quant-pharXiv:2610.31283•Oct 23, 2026•0 citations

Maximal entanglement generation in spectrally distinct solid state qubits

Elena Callus, Pieter Kok

We demonstrate how to create maximal entanglement between two qubits that are encoded in two spectrally distinct solid-state quantum emitters embedded in a waveguide interferometer. The optical probe is provided by readily accessible squeezed light, generated by parametric down-conversion. By continuously probing the emitters, the photon scattering builds up entanglement with a concurrence that reaches its maximum after O(10^1) photo-detection events. Our method does not require perfectly identical emitters, and accommodates spectral variations due to the fabrication process. It is also robust enough to create entanglement with a concurrence above 99% for 10% scattering photon loss, and can form the basis for practical entangled networks.

•Feb 24, 2021•0 citations

Generating Maximal Entanglement between Spectrally Distinct Solid-State Emitters

Kristoffer B. Joanesarson, David L. Hurst, Jake Iles-Smith +2 more

Quantum entanglement is an important and often necessary resource for quantum information processing e.g. the measurement-based quantum computer [1]. Current protocols for generating entanglement between emitters assume near identical spectral properties [2-3], which is a major obstacle for using integrated solid-state emitters in photonic structures as a scalable platform. The solid-state emitters can vary significantly from one another in terms of both lifetimes and central energies due to imperfections during fabrication and therefore need to be tuned into resonance e.g. electrically [4]. The requirement for local tuning of emitters provides a barrier to scalability.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2019•0 citations

Deterministic Generation of Large-Scale Entangled Photonic Cluster State from Interacting Solid State Emitters

Mercedes Gimeno-Segovia, Terry Rudolph, Sophia E. Economou

The ability to create large highly entangled "cluster" states is crucial for measurement-based quantum computing. We show that deterministic multiphoton entanglement can be created from coupled solid state quantum emitters without the need for any two-qubit gates and regardless of whether the emitters are identical. In particular, we present a general method for controlled entanglement creation by making direct use of the always-on exchange interaction, in combination with single-qubit operations. This is used to provide a recipe for the generation of two-dimensional, cluster-state entangled photons that can be carried out with existing experimental capabilities in quantum dots.

arXiv:1801.02599•Physical Review Letters•Aug 12, 2019•75 citations

Realization of waveguide many-body quantum optics

Lena M. Hansen, Clara Henke, Christoph Hotter +13 more

Controlling light photon-by-photon is central to quantum optics. At a fundamental level, photon interactions are mediated by their coupling to atoms, and ultimate control requires deterministic light-matter interfacing of single photons to single atoms. Extending this paradigm to radiatively couple multiple individual atoms in a deterministic and scalable manner opens the arena of many-body quantum optics. Here, we realize such a setting by coherently coupling solid-state artificial atoms to a nanophotonic waveguide and demonstrate higher-order photon correlations that are controlled by the number of quantum emitters. We study the scaling of nonlinear photonic transport induced by emitter-photon scattering and demonstrate that adding a quantum emitter generates higher-order photon correlations. Specifically, we experimentally observe genuine three-photon correlations from a pair of collectively coupled emitters, while contributions from lower photon numbers are suppressed. In addition, we scale to three resonant quantum emitters coupled to the waveguide. These advancements demonstrate the onset of many-body quantum optics in waveguide quantum electrodynamics, enabling new photonic quantum simulators, the creation of many-body entangled states, and the exploration of novel quantum phase transitions.

quant-pharXiv:2605.18525•May 19, 2026•0 citations
We show how to create maximal entanglement between spectrally distinct solid-state emitters embedded in a waveguide interferometer. By revealing the rich underlying structure of multiphoton scattering in emitters, we show that a two-photon input state can generate deterministic maximal entanglement even for emitters with significantly different transition energies and linewidths. The optimal frequency of the input is determined by two competing processes: which-path erasure and interaction strength. We find that smaller spectral overlap can be overcome with higher photon numbers, and quasimonochromatic photons are optimal for entanglement generation. Our work provides a new methodology for solid-state entanglement generation, where the requirement for perfectly matched emitters can be relaxed in favor of optical state optimization.
We demonstrate how to create maximal entanglement between two qubits that are encoded in two spectrally distinct solid-state quantum emitters embedded in a waveguide interferometer. The optical probe is provided by readily accessible squeezed light, generated by parametric down-conversion. By continuously illuminating the emitters, the photon scattering and incremental path-erasure builds up entanglement. Our method does not require perfectly identical emitters, and accommodates spectral variations due to the fabrication process. Furthermore, for some linewidth and energy ratios, the entanglement buildup can be significantly faster than for more similar emitters. It is also robust enough to create entanglement with a concurrence above 99% in the event of scattering losses and detector inefficiencies and can form the basis for practical entangled networks.
Solid state quantum emitters with electronic spin properties can be entangled using optical interferometric which-path erasure techniques that rely on identical frequencies and linewidths of the emitters. This promises a powerful, fast and scalable platform for quantum technologies. Using current protocols, a pair of emitters embedded in a waveguide interferometer can be deterministically prepared in a maximally entangled state. However, the amount of entanglement diminishes rapidly with increasing separation of the emission lines and variations in the linewidths of the emitters. Solid state emitters such as quantum dots are subject to intrinsic variations in the fabrication process. Therefore, manufacturing the required number of identical emitters on a chip is not scalable. In this Letter, we present a method that uses readily available pairs of entangled photons to entangle solid state emitters with large transition frequency separations and linewidth variations, circumventing the need to fabricate optically identical emitters. We demonstrate a concurrence of C = 0.95 for typical quantum dots using narrowband photon inputs.
We demonstrate how to create maximal entanglement between two qubits that are encoded in two spectrally distinct solid-state quantum emitters embedded in a waveguide interferometer. The optical probe is provided by readily accessible squeezed light, generated by parametric down-conversion. By continuously probing the emitters, the photon scattering builds up entanglement with a concurrence that reaches its maximum after O(10^1) photo-detection events. Our method does not require perfectly identical emitters, and accommodates spectral variations due to the fabrication process. It is also robust enough to create entanglement with a concurrence above 99% for 10% scattering photon loss, and can form the basis for practical entangled networks.
Quantum entanglement is an important and often necessary resource for quantum information processing e.g. the measurement-based quantum computer [1]. Current protocols for generating entanglement between emitters assume near identical spectral properties [2-3], which is a major obstacle for using integrated solid-state emitters in photonic structures as a scalable platform. The solid-state emitters can vary significantly from one another in terms of both lifetimes and central energies due to imperfections during fabrication and therefore need to be tuned into resonance e.g. electrically [4]. The requirement for local tuning of emitters provides a barrier to scalability.
The ability to create large highly entangled "cluster" states is crucial for measurement-based quantum computing. We show that deterministic multiphoton entanglement can be created from coupled solid state quantum emitters without the need for any two-qubit gates and regardless of whether the emitters are identical. In particular, we present a general method for controlled entanglement creation by making direct use of the always-on exchange interaction, in combination with single-qubit operations. This is used to provide a recipe for the generation of two-dimensional, cluster-state entangled photons that can be carried out with existing experimental capabilities in quantum dots.
Controlling light photon-by-photon is central to quantum optics. At a fundamental level, photon interactions are mediated by their coupling to atoms, and ultimate control requires deterministic light-matter interfacing of single photons to single atoms. Extending this paradigm to radiatively couple multiple individual atoms in a deterministic and scalable manner opens the arena of many-body quantum optics. Here, we realize such a setting by coherently coupling solid-state artificial atoms to a nanophotonic waveguide and demonstrate higher-order photon correlations that are controlled by the number of quantum emitters. We study the scaling of nonlinear photonic transport induced by emitter-photon scattering and demonstrate that adding a quantum emitter generates higher-order photon correlations. Specifically, we experimentally observe genuine three-photon correlations from a pair of collectively coupled emitters, while contributions from lower photon numbers are suppressed. In addition, we scale to three resonant quantum emitters coupled to the waveguide. These advancements demonstrate the onset of many-body quantum optics in waveguide quantum electrodynamics, enabling new photonic quantum simulators, the creation of many-body entangled states, and the exploration of novel quantum phase transitions.