Related Experiment Video
Updated: Aug 13, 2025
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
8.6K
Entangled States Are Harder to Transfer than Product States
Tony J G Apollaro1, Salvatore Lorenzo2, Francesco Plastina3,4
1Department of Physics, University of Malta, MSD 2080 Msida, Malta.
Entropy (Basel, Switzerland)
|January 21, 2023
Summary
Distributing entangled quantum states is less efficient than product states. Genuine multipartite entanglement significantly reduces fidelity more than two-qubit entanglement in quantum channels.
Area of Science:
- Quantum Information Science
- Quantum Communication Protocols
- Quantum State Distribution
Background:
- Entangled state distribution is crucial for quantum information processing.
- Current methods often involve creating states centrally and transmitting them via quantum channels.
- Quantifying the fidelity loss due to entanglement during distribution has been lacking.
Purpose of the Study:
- To quantify the inefficiency in distributing entangled quantum states compared to product states.
- To analyze the impact of different types of entanglement on state transfer fidelity.
- To investigate the relationship between fidelity and the number of qubits in quantum channels.
Main Methods:
- Considered n-independent amplitude-damping channels acting on n-qubit states.
- Derived exact analytical results for fidelity decrease.
- Focused on systems with up to four qubits.
Main Results:
- Entangled states show a fidelity decrease compared to product states.
- Genuine multipartite entanglement has a more detrimental effect on fidelity than two-qubit entanglement.
- For larger systems, fidelity difference increases with single-qubit fidelity.
Conclusions:
- The study quantifies the fidelity loss in distributing entangled states through amplitude-damping channels.
- Multipartite entanglement poses a greater challenge to state distribution fidelity than bipartite entanglement.
- Single-qubit fidelity may be an unreliable metric for assessing larger entangled quantum systems.
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