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Published on: November 11, 2013
Heralded single-magnon quantum memory for photon polarization States
Haruka Tanji1, Saikat Ghosh, Jonathan Simon
1Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Physical Review Letters
|August 8, 2009
Summary
Researchers created a quantum memory storing light polarization in atomic spin waves. This quantum memory can regenerate the photon
Area of Science:
- Quantum physics
- Atomic physics
- Quantum optics
Background:
- Quantum memory is crucial for quantum information processing.
- Storing photonic quantum states in matter systems is challenging.
Purpose of the Study:
- To demonstrate a heralded quantum memory for light polarization states.
- To achieve high-fidelity storage and retrieval of photonic polarization.
Main Methods:
- Mapping photon polarization to a collective-spin excitation (magnon) in two atomic ensembles.
- Using a heralded process where a photon signals the storage event.
- Converting the magnon back into a photon at a later time.
Main Results:
- Achieved polarization fidelity over 90(2)% for regenerated photons.
- Fidelity significantly exceeds the classical limit of 2/3.
- Demonstrated a nondestructive quantum probe for light polarization.
Conclusions:
- The demonstrated quantum memory is a significant step towards robust quantum information processing.
- The high fidelity and nondestructive nature open possibilities for quantum networks and sensing.
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