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Coherence distillation machines are impossible in quantum thermodynamics
1Departments of Physics & Electrical and Computer Engineering, Duke University, Durham, NC, 27708, USA. iman.marvian@duke.edu.
Nature Communications
|January 9, 2020
Summary
Quantum coherence distillation is impossible at a nonzero rate for mixed states, even with work. However, sub-linear pure coherent states can be distilled with vanishing error.
Area of Science:
- Quantum Thermodynamics
- Quantum Information Theory
Background:
- Coherence in quantum thermodynamics is a resource independent of work.
- The existence of a coherence distillation machine remains an open question.
Purpose of the Study:
- To investigate if quantum mechanics and thermodynamics permit a coherence distillation machine.
- To determine if pure coherent states can be obtained from mixed states at a nonzero rate, potentially consuming work.
Main Methods:
- Theoretical analysis of quantum mechanics and thermodynamics laws.
- Investigation of coherence distillation for generic (full-rank) mixed states.
Main Results:
- The answer is negative: a coherence distillation machine cannot operate at a nonzero rate for generic mixed states.
- It is impossible to distill synchronized quantum clocks in pure states from noisy copies at a nonzero rate.
Conclusions:
- Coherence distillation is fundamentally limited for mixed quantum states.
- Sub-linear quantities of pure coherent states can be distilled with vanishing error, indicating partial distillability.
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