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Error distributions on large entangled states with non-Markovian dynamics.
Dara P S McCutcheon1, Netanel H Lindner2, Terry Rudolph3
1Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom and Departamento de Física, FCEyN, UBA and IFIBA, Conicet, Pabellón 1, Ciudad Universitaria, 1428 Buenos Aires, Argentina and Department of Photonics Engineering, DTU Fotonik, Ørsteds Plads, 2800 Kongens Lyngby, Denmark.
Physical Review Letters
|January 24, 2015
Summary
We found that errors in quantum computations using non-Markovian emitters can be bounded by simple models. This suggests current accuracy thresholds are still effective for these complex quantum systems.
Area of Science:
- Quantum information science
- Quantum computing error analysis
- Non-Markovian quantum dynamics
Background:
- Quantum computations rely on entangled states, which are susceptible to errors.
- Understanding error distributions is crucial for developing robust quantum algorithms.
- Non-Markovian environments introduce complex error correlations.
Purpose of the Study:
- To analyze the error distribution in entangled states generated by non-Markovian emitters.
- To determine the effectiveness of Markovian error models for non-Markovian systems.
- To assess the validity of current accuracy threshold theorems.
Main Methods:
- Investigated error patterns in entangled states from emitters with strong non-Markovian evolution.
- Analyzed emitter-environment coupling, specifically pure-dephasing.
- Developed theoretical bounds for error probabilities.
Main Results:
- For pure-dephasing, error probability patterns are bounded by a Markovian form.
- Accuracy threshold theorems based on Markovian models remain effective.
- Even complex error structures beyond pure-dephasing can be qualitatively bounded by Markovian models.
Conclusions:
- Markovian error models provide a useful framework for bounding errors in non-Markovian quantum systems.
- Existing quantum accuracy threshold theorems are likely applicable to non-Markovian scenarios.
- Further research can explore the quantitative bounds for non-Markovian error structures.
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