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Updated: Nov 6, 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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Direct observation of deterministic macroscopic entanglement.
Shlomi Kotler1,2, Gabriel A Peterson3,2, Ezad Shojaee3,2
1National Institute of Standards and Technology, Boulder, CO 80305, USA. shlomi.kotler@mail.huji.ac.il.
Science (New York, N.Y.)
|May 7, 2021
Summary
Researchers achieved quantum entanglement between two macroscopic mechanical drumheads. This breakthrough in quantum mechanics enables new possibilities for sensing and quantum networks.
Area of Science:
- Quantum mechanics
- Macroscopic quantum phenomena
- Optomechanics
Background:
- Quantum entanglement is a phenomenon where particles exhibit correlated behavior, regardless of distance.
- Observing entanglement in macroscopic systems is challenging due to increased mass and stringent measurement requirements.
Purpose of the Study:
- To deterministically entangle two macroscopic mechanical systems.
- To demonstrate quantum entanglement in micro-objects with significant mass.
Main Methods:
- Utilized pulsed electromechanics for precise control and measurement.
- Performed nearly quantum-limited measurements of position and momentum quadratures.
- Employed quantum state tomography to verify entanglement.
Main Results:
- Successfully achieved deterministic quantum entanglement between two 70-picogram mechanical drumheads.
- Directly observed entanglement through quantum state tomography.
- Demonstrated control over macroscopic mechanical systems at the quantum level.
Conclusions:
- Entangled macroscopic systems open new avenues for fundamental tests of quantum mechanics.
- These systems can enhance sensing capabilities beyond the standard quantum limit.
- They are suitable for use as robust nodes in future quantum networks.
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