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Geometric entangling gates in decoherence-free subspaces with minimal requirements
Xun-Li Feng1, Chunfeng Wu, Hui Sun
1Department of Physics and Centre for Quantum Technologies, National University of Singapore, 2 Science Drive 3, Singapore 117542.
Physical Review Letters
|April 7, 2010
Summary
We present a novel atom-cavity interaction scheme for robust quantum entanglement. This method utilizes decoherence-free subspaces (DFSs) and geometric phase to create entangling gates for two logical qubits with minimal dephasing.
Area of Science:
- Quantum Information Science
- Atomic Physics
- Cavity Quantum Electrodynamics
Background:
- Quantum entanglement is crucial for quantum computation and communication.
- Decoherence limits the performance of quantum systems.
- Decoherence-free subspaces (DFSs) offer a robust approach to mitigate environmental noise.
Purpose of the Study:
- To introduce a new strongly driven dispersive atom-cavity interaction.
- To develop a novel scheme for implementing nontrivial entangling gates for two logical qubits within DFSs.
- To leverage the advantages of DFS and geometric phase for robust quantum gate operations.
Main Methods:
- Utilizing a strongly driven dispersive atom-cavity interaction.
- Implementing a scheme that combines DFS properties with geometric phase.
- Focusing on collective dephasing of only two neighboring physical qubits encoding a logical qubit.
Main Results:
- Successfully developed a new scheme for implementing nontrivial entangling gates.
- Demonstrated the combination of DFS robustness and geometric phase for enhanced gate fidelity.
- Showcased a method requiring minimal physical qubit interaction for dephasing.
Conclusions:
- The proposed scheme offers a robust method for creating entangling gates for logical qubits.
- The integration of DFS and geometric phase provides a powerful strategy for fault-tolerant quantum information processing.
- This approach advances the development of practical quantum computing architectures.
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