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Published on: November 11, 2013
Assisted Distillation of Quantum Coherence.
E Chitambar1, A Streltsov2, S Rana2
1Department of Physics and Astronomy, Southern Illinois University, Carbondale, Illinois 62901, USA.
We introduce assisted coherence distillation, where two parties collaborate to maximize coherence in one system using specific quantum operations. The distillation rate equals the coherence of assistance, offering a new view on von Neumann entropy.
Area of Science:
- Quantum Information Science
- Quantum Thermodynamics
- Quantum Foundations
Background:
- Coherence is a key resource in quantum mechanics, essential for quantum computation and information processing.
- Assisted processes, involving collaboration between multiple systems or parties, are crucial for enhancing quantum tasks.
- Understanding the limits of coherence generation and manipulation is vital for advancing quantum technologies.
Purpose of the Study:
- To introduce and analyze the novel task of assisted coherence distillation.
- To define and characterize 'coherence of assistance' as a fundamental quantity in this process.
- To explore the connection between coherence distillation, von Neumann entropy, and multipartite quantum systems.
Main Methods:
- Development of the theoretical framework for assisted coherence distillation.
- Introduction of local quantum-incoherent operations and classical communication (LQICC) as the operational paradigm.
- Mathematical characterization of the asymptotic rate of distillation for pure states.
Main Results:
- The asymptotic rate of assisted coherence distillation for pure states is proven to be equal to the coherence of assistance.
- Properties of coherence of assistance are derived, analogous to entanglement of assistance.
- A novel interpretation of von Neumann entropy is proposed: it quantifies the maximum achievable gain in quantum coherence through assistance.
Conclusions:
- Assisted coherence distillation provides a new perspective on quantifying and generating quantum coherence.
- The concept of coherence of assistance offers a valuable tool for understanding quantum correlations.
- The findings have implications for quantum information processing, quantum thermodynamics, and the fundamental understanding of quantum entropy.
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