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Published on: November 12, 2013
Construction and implementation of NMR quantum logic gates for two spin systems
M D Price1, S S Somaroo, C H Tseng
1Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts 02139, USA.
Researchers developed a systematic method to create nuclear magnetic resonance (NMR) pulse sequences for quantum logic gates. This advance simplifies building prototype quantum computers using NMR measurements.
Area of Science:
- Quantum Computing
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Quantum Information Science
Background:
- Ensemble quantum computing using NMR measurements is a key method for studying small quantum computer prototypes.
- Access to a diverse set of logic gates is crucial for laboratory-based quantum computing research.
- Developing efficient methods to translate quantum logic operations into experimental protocols is essential.
Purpose of the Study:
- To introduce a systematic approach for reducing quantum logic gates into NMR pulse sequences.
- To provide a method for generating pulse sequences for all permutations of a four-level quantum system.
- To experimentally implement representative quantum logic operations using NMR.
Main Methods:
- Representing quantum logic operations as permutation matrices derived from their truth tables.
- Utilizing these permutation matrices as propagators for NMR transitions.
- Deriving NMR pulse sequences from the calculated propagators.
- Implementing derived pulse sequences on a 13C-labeled chloroform system (a two spin-1/2 system).
Main Results:
- A systematic methodology for deriving NMR pulse sequences from quantum logic gates was established.
- Pulse sequences for all permutations of a four-level system were successfully derived.
- Experimental implementations of selected quantum logic operations were demonstrated on a NMR system.
Conclusions:
- The developed approach provides a direct and systematic route from quantum logic operations to NMR pulse sequences.
- This method facilitates the construction and testing of quantum logic gates for NMR-based quantum computing.
- The experimental validation confirms the feasibility and effectiveness of the proposed technique for quantum information processing.
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