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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
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Practical Entanglement Estimation for Spin-System Quantum Simulators
O Marty1, M Cramer1, M B Plenio1
1Institut für Theoretische Physik & IQST, Albert-Einstein-Allee 11, Universität Ulm, Germany.
Physical Review Letters
|March 26, 2016
Summary
We developed practical methods to measure quantum entanglement in simulators using common experimental tools. These techniques provide reliable entanglement bounds for benchmarking quantum devices.
Area of Science:
- Quantum Information Science
- Quantum Simulation
- Condensed Matter Physics
Background:
- Entanglement is crucial for quantum simulation but difficult to measure.
- Realistic quantum simulators face challenges like noise and temperature (mixedness).
Purpose of the Study:
- To present practical methods for measuring entanglement in quantum simulators.
- To develop entanglement measurement schemes applicable to trapped ions, cold atoms, and superconducting qubits.
- To address challenges posed by mixed states in realistic experimental conditions.
Main Methods:
- Focus on long- and short-range Ising-type Hamiltonians.
- Identify a single observable as a lower bound for entanglement, measurable via a simple quantum circuit.
- Evaluate routinely measured observables as quantitative entanglement witnesses.
Main Results:
- A single, simple-to-measure observable provides a lower bound for entanglement.
- Established methods for using standard observables as entanglement witnesses under realistic conditions.
- Demonstrated applicability to various quantum simulation platforms.
Conclusions:
- The proposed methods offer practical routes to quantify entanglement in quantum simulators.
- These techniques facilitate experimental studies of entanglement scaling and benchmarking of quantum devices.
- Enables reliable characterization of quantum simulator performance.
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