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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Atomic vapor quantum memory for a photonic polarization qubit
1Department of Physics, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Optics Express
|December 18, 2010
Summary
Researchers created an atomic vapor quantum memory storing photonic polarization qubits. This quantum memory, using electromagnetically-induced transparency in warm Rubidium atoms, achieved over 0.91 fidelity for 16 μs.
Area of Science:
- Quantum Information Science
- Atomic Physics
- Quantum Optics
Background:
- Quantum memories are crucial for quantum communication and computation.
- Storing photonic qubits in atomic ensembles is a promising approach.
Purpose of the Study:
- To experimentally realize and characterize an atomic vapor quantum memory for photonic polarization qubits.
- To evaluate the performance of the memory using quantum process tomography.
Main Methods:
- Utilized electromagnetically-induced transparency (EIT) in warm Rubidium atoms.
- Employed two spatially separated atomic ensembles within a single vapor cell.
- Characterized the quantum memory performance using quantum process tomography.
Main Results:
- Achieved a process fidelity greater than 0.91.
- Demonstrated successful storage of photonic polarization qubits for up to 16 microseconds.
Conclusions:
- The experimental realization demonstrates a viable atomic vapor quantum memory for polarization qubits.
- The achieved fidelity and storage time show potential for practical quantum information applications.
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