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Updated: May 25, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Entanglement can completely defeat quantum noise.
Jianxin Chen1, Toby S Cubitt, Aram W Harrow
1Department of Mathematics & Statistics, U. of Guelph, Guelph, Ontario, Canada.
Physical Review Letters
|January 17, 2012
Summary
Two quantum channels, individually error-prone, can perfectly transmit quantum information together. This demonstrates zero-error quantum communication superactivation, a novel use of entanglement to combat noise.
Area of Science:
- Quantum Information Science
- Quantum Communication
- Quantum Error Correction
Background:
- Classical information theory often assumes channels have a fixed capacity.
- Quantum channels can exhibit superadditivity, where combined use exceeds individual capacities.
- Superactivation is a phenomenon where zero-capacity channels can transmit information via entanglement.
Purpose of the Study:
- To demonstrate zero-error classical capacity superactivation.
- To show that entanglement enables perfect zero-error quantum communication over noisy channels.
- To introduce a new form of superactivation involving shared entanglement between sender and receiver.
Main Methods:
- Investigated the properties of two specific quantum channels.
- Analyzed the combined performance of these channels using entangled inputs.
- Quantified the error probability for classical and quantum information transmission.
Main Results:
- Two individually unreliable quantum channels were shown to achieve perfect quantum information transmission when used together.
- This constitutes a strong form of superactivation, enabling zero-error quantum communication.
- A novel superactivation effect was observed with entanglement shared between sender and receiver.
Conclusions:
- Entanglement can be leveraged to achieve perfect quantum communication over noisy channels.
- The study provides a new understanding of superactivation in quantum information theory.
- Shared entanglement offers a powerful resource for robust quantum information processing.
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