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Experimental study of Forrelation in nuclear spins.
1State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China; Collaborative Innovation Centre of Quantum Matter, Beijing 100084, China.
Science Bulletin
|January 20, 2023
Summary
Researchers experimentally probed Forrelation functions using nuclear spins, demonstrating a quantum query algorithm
Area of Science:
- Quantum Information Science
- Quantum Computing
- Quantum Algorithms
Background:
- Correlation functions quantify relationships in data.
- Forrelation functions, a new class, are key to quantum query complexity.
- A quantum algorithm offers exponential speedup for 2-fold Forrelation problems.
Purpose of the Study:
- To experimentally investigate 2-fold and 3-fold Forrelation functions.
- To assess the feasibility of quantum query algorithms in a realistic experimental setting.
- To evaluate the potential for demonstrating quantum supremacy with current technology.
Main Methods:
- Encoding Forrelation functions in nuclear spin systems.
- Utilizing optimized GRAPE pulse sequences for precise spin control.
- Managing and controlling spin fluctuations within a critical threshold.
Main Results:
- Successful experimental probing of 2-fold and 3-fold Forrelations.
- Demonstration of controlled spin fluctuations using optimized pulse sequences.
- Validation of the quantum query algorithm's accuracy in the presence of experimental noise.
Conclusions:
- The experimental implementation validates the quantum query algorithm for Forrelation.
- The study indicates quantum supremacy is achievable for Forrelation problems with current technology.
- This work paves the way for further experimental studies in quantum query complexity.
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