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Published on: August 2, 2019
CNOT and Bell-state analysis in the weak-coupling cavity QED regime
Cristian Bonato1, Florian Haupt, Sumant S R Oemrawsingh
1Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
Physical Review Letters
|May 21, 2010
Summary
We propose a new quantum interface for photon-electron spin interaction in quantum dots. This interface enables quantum computing applications like CNOT gates and entanglement, with current technological feasibility.
Area of Science:
- Quantum Optics
- Quantum Information Science
- Solid-State Physics
Background:
- Quantum dots offer controllable electron spin states.
- Microcavities enhance light-matter interactions.
- Weak coupling is crucial for specific quantum phenomena.
Purpose of the Study:
- To propose a novel interface for photon-electron spin interaction.
- To demonstrate its application in quantum information processing.
- To assess the experimental viability of the proposed scheme.
Main Methods:
- Utilizing spin-selective photon reflection from a microcavity.
- Confining an electron's spin within a quantum dot.
- Operating the system in the weak-coupling regime.
Main Results:
- A functional interface between photon and electron spins is proposed.
- The interface supports the construction of CNOT gates.
- It enables the creation of multiphoton entanglers and photonic Bell-state analyzers.
Conclusions:
- The proposed quantum interface is theoretically sound.
- It offers pathways for advanced quantum information protocols.
- The scheme is feasible with existing experimental technologies.
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