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Updated: Jun 14, 2026
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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Demonstration of atomic frequency comb memory for light with spin-wave storage
Mikael Afzelius1, Imam Usmani, Atia Amari
1Group of Applied Physics, University of Geneva, CH-1211 Geneva 4, Switzerland. mikael.afzelius@unige.ch
Physical Review Letters
|April 7, 2010
Summary
Researchers demonstrated light storage using a praseodymium-doped crystal, converting optical pulses into spin-wave excitations and back. This novel method stores light for up to 20 microseconds, crucial for quantum communication.
Area of Science:
- Quantum optics
- Solid-state quantum memory
Background:
- Storing quantum information is vital for quantum networks.
- Atomic frequency combs offer a promising platform for optical memory.
Purpose of the Study:
- To demonstrate efficient light storage and retrieval using a praseodymium-doped crystal.
- To explore the potential of this system for quantum communication applications.
Main Methods:
- Utilized a praseodymium-doped crystal with an atomic frequency comb structure.
- Converted optical pulses to spin-wave excitations using control pulses.
- Retrieved stored light via a photon-echo mechanism.
Main Results:
- Achieved storage of submicrosecond optical pulses for up to 20 microseconds.
- Demonstrated on-demand retrieval of the stored light.
- The atomic frequency comb enabled photon-echo-type rephasing.
Conclusions:
- The combined photon-echo and spin-wave storage scheme is effective for light storage.
- This technique shows potential for storing multiple temporal modes in the single-photon regime.
- The system is a valuable resource for developing quantum repeaters for long-distance quantum communication.
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