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Generation and Coherent Control of Pulsed Quantum Frequency Combs
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Quantum Process Fidelity Bounds from Sets of Input States
Karl Mayer1, Emanuel Knill2,3
1Department of Physics, University of Colorado, Boulder, Colorado, USA.
Physical Review. A
|December 14, 2020
Summary
This study introduces a method to estimate quantum process fidelity using input-output state fidelities. It offers an efficient alternative to full process tomography, especially for symmetric POVMs.
Area of Science:
- Quantum Information Science
- Quantum Computing
- Quantum Process Characterization
Background:
- Estimating quantum process fidelity is crucial for quantum information processing.
- Full process tomography can be resource-intensive.
- Bounds on fidelity are needed for efficient characterization.
Purpose of the Study:
- To develop a method for bounding quantum process fidelity.
- To provide an efficient alternative to full process tomography.
- To analyze fidelity bounds for specific input state sets.
Main Methods:
- Formulating the problem as a semidefinite program.
- Proving convexity of minimum process fidelity.
- Deriving fidelity bounds for small errors and symmetric POVMs.
Main Results:
- Established a convex optimization framework for fidelity bounding.
- Derived conditions for unique process determination.
- Showed minimum fidelity is linearly bounded by average output error for symmetric POVMs.
- Identified efficient estimation methods using symmetric POVMs.
Conclusions:
- The proposed method provides an efficient way to estimate quantum process fidelity.
- Symmetric POVMs offer a practical approach for fidelity estimation.
- This work reduces the experimental overhead for quantum process characterization.
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