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Updated: Dec 7, 2025
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Path identity as a source of high-dimensional entanglement
Jaroslav Kysela1,2, Manuel Erhard1,2, Armin Hochrainer3,2
1Faculty of Physics, Vienna Center for Quantum Science & Technology, University of Vienna, 1090 Vienna, Austria; anton.zeilinger@univie.ac.at jaroslav.kysela@univie.ac.at manuel.erhard@univie.ac.at.
Summary
We demonstrate a new quantum entanglement framework, "entanglement by path identity," enabling customizable, high-dimensional entangled photon pairs. This approach is versatile for future quantum technologies and fundamental physics experiments.
Area of Science:
- Quantum Information Science
- Quantum Optics
- Quantum Entanglement
Background:
- Quantum entanglement is crucial for quantum technologies, but generating specific entangled states can be challenging.
- Existing methods often tie entanglement properties to the physical generation process.
Purpose of the Study:
- To experimentally demonstrate a general entanglement generation framework independent of the physical process.
- To introduce and utilize the 'entanglement by path identity' framework for customizable quantum states.
- To develop a modular source for high-dimensionally entangled photon pairs.
Main Methods:
- Utilizing indistinguishability of generation processes and setup geometry to create entanglement.
- Employing specific geometries within the 'entanglement by path identity' framework.
- Building a modular photon pair source to generate high-dimensional entanglement in orbital angular momentum.
Main Results:
- Demonstrated creation of three-dimensionally entangled states using the new framework.
- Showcased incremental increase in entanglement dimensionality while maintaining state quality.
- Developed a modular source adaptable to various degrees of freedom and integrated devices.
Conclusions:
- The 'entanglement by path identity' framework offers a customizable and general approach to generating quantum entanglement.
- The modular source design facilitates the creation of high-quality, high-dimensional entangled states.
- This approach is expected to benefit future quantum technologies and fundamental tests in higher dimensions.
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