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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Realizing a deterministic source of multipartite-entangled photonic qubits.
Jean-Claude Besse1, Kevin Reuer2, Michele C Collodo2
1Department of Physics, ETH Zurich, Zurich, CH-8093, Switzerland. jbesse@phys.ethz.ch.
Nature Communications
|September 28, 2020
Summary
Researchers deterministically generated multi-mode photonic entangled states, including cluster, GHZ, and W states. This breakthrough overcomes challenges in quantum information processing and many-body physics research.
Area of Science:
- Quantum Information Science
- Quantum Many-Body Physics
- Quantum Optics
Background:
- Entangled electromagnetic radiation is crucial for quantum information processing.
- Generating multi-mode entangled states with large entanglement length deterministically remains a significant challenge.
- Existing methods are often probabilistic or limited to specific state types.
Purpose of the Study:
- To demonstrate the deterministic generation of purely photonic entangled states.
- To overcome limitations of probabilistic and state-specific generation methods.
- To advance the study of quantum many-body physics using controlled entangled states.
Main Methods:
- Sequential emission of microwave photons from a controlled auxiliary system into a waveguide.
- Tomographic reconstruction of quantum many-body states for up to N=4 photonic modes.
- Process tomography to infer quantum states for larger N.
Main Results:
- Fully deterministic generation of cluster, GHZ, and W entangled states.
- Successful tomographic reconstruction of multi-mode photonic states.
- Estimation of localizable entanglement persisting over approximately ten photonic qubits.
Conclusions:
- The developed method enables deterministic, versatile generation of multi-mode photonic entangled states.
- This technique provides a powerful tool for quantum information processing and quantum simulation.
- The ability to generate and control complex entangled states opens new avenues for fundamental physics research.
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