Related Experiment Video
Updated: May 31, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
No-Broadcasting of Non-Gaussian States.
Kaustav Chatterjee1, Ulrik Lund Andersen1
1Technical University of Denmark, Center for Macroscopic Quantum States (bigQ), Department of Physics, Building 307, Fysikvej, 2800 Kongens Lyngby, Denmark.
Physical Review Letters
|May 29, 2026
Summary
Broadcasting non-Gaussian states using only Gaussian operations is impossible. This finding impacts quantum technologies by showing non-Gaussian states cannot be freely cloned, even with advanced quantum control theory.
Area of Science:
- Quantum Information Science
- Continuous-Variable Quantum Systems
- Quantum Resource Theory
Background:
- Gaussian states are fundamental in continuous-variable quantum systems due to their accessibility and simple mathematical representation.
- Quantum technologies often necessitate non-Gaussian states, which are considered valuable resources in quantum resource theory.
- Gaussian operations are classified as 'free' in this resource framework, while non-Gaussian states are 'resources'.
Purpose of the Study:
- To investigate the possibility of broadcasting non-Gaussian states using only Gaussian operations.
- To determine if the resource content of non-Gaussian states can be meaningfully cloned under Gaussian dynamics.
- To explore the implications of broadcasting limitations for quantum information processing and quantum technologies.
Main Methods:
- Demonstrated that the relative entropy of non-Gaussianity is not superadditive, precluding its use in certain no-go theorems.
- Employed fixed points of Gaussian operations and concepts from control theory to prove the broadcasting impossibility.
- Analyzed the implications for systems interacting via Gaussian dynamics, showing irreversible transfer of non-Gaussianity.
Main Results:
- Proved that broadcasting of non-Gaussian states via Gaussian operations is fundamentally not possible.
- Established that if one subsystem gains non-Gaussianity through Gaussian interaction, the other must irreversibly lose it.
- Commented on the broadcasting of Wigner negativity and genuine quantum non-Gaussianity within the framework of Gaussian free operations.
Conclusions:
- Non-Gaussian states cannot be cloned or broadcast using only the 'free' set of Gaussian operations.
- This limitation has significant consequences for the development and implementation of quantum technologies requiring non-Gaussian resources.
- The study provides a crucial understanding of resource manipulation in quantum systems, highlighting the distinct nature of non-Gaussian states.
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