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Experimental long-lived entanglement of two macroscopic objects.
B Julsgaard1, A Kozhekin, E S Polzik
1Institute of Physics and Astronomy, University of Aarhus, Denmark.
Nature
|September 28, 2001
Summary
Researchers demonstrate quantum entanglement between two macroscopic objects, each containing billions of atoms. This robust, long-lived entanglement in large systems opens new avenues for quantum information processing and quantum memory applications.
Area of Science:
- Quantum Mechanics
- Quantum Optics
- Atomic Physics
Background:
- Entanglement is a fundamental quantum phenomenon where systems are linked regardless of distance.
- Entanglement is typically observed in microscopic systems, limiting its application in macroscopic settings.
Purpose of the Study:
- To experimentally demonstrate quantum entanglement between two macroscopic objects.
- To explore the potential of macroscopic entanglement for quantum technologies.
Main Methods:
- Generated entanglement using a light pulse to perform a non-local Bell measurement on collective atomic spins.
- Utilized two caesium gas samples, each containing approximately 10^12 atoms.
Main Results:
- Successfully achieved and verified entanglement between the two macroscopic caesium gas samples.
- Maintained the entangled spin-state for up to 0.5 milliseconds, demonstrating robustness and longevity.
Conclusions:
- Macroscopic quantum entanglement is achievable and can be sustained for significant durations.
- This breakthrough provides a foundation for scalable quantum information processing, including quantum teleportation and quantum memory.
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