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Updated: Nov 27, 2025
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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
13.1K
Understanding of Collective Atom Phase Control in Modified Photon Echoes for a Near-Perfect Storage Time-Extended
Rahmat Ullah1,2, Byoung S Ham1
1Center for Photon Information Processing, and School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju 61005, Korea.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
This study analyzes a photon echo quantum memory protocol using a three-level system. It demonstrates classical control over quantum state phase and propagation direction via manipulated control pulses.
Area of Science:
- Quantum Information Science
- Atomic, Molecular, and Optical Physics
Background:
- Photon echo-based quantum memory offers promising avenues for quantum information storage.
- Three-level systems present unique dynamics for manipulating quantum states.
Purpose of the Study:
- To analyze a near-perfect storage time-extended photon echo quantum memory protocol in a three-level system.
- To investigate the classical controllability of quantum state phase and propagation direction.
Main Methods:
- Solving the Maxwell-Bloch equations for a backward photon echo scheme.
- Implementing controlled coherence conversion via Rabi flopping.
- Analyzing single and double rephasing photon echo schemes.
Main Results:
- Demonstrated coherent determination of photon echo propagation direction via phase-matching.
- Showcased classical control over quantum state phase and propagation by manipulating control pulses.
- Identified limitations in Maxwell-Bloch equations for three-level systems regarding phase changes with arbitrary control pulse areas.
Conclusions:
- The backward photon echo scheme in a three-level system enables classical control over quantum state properties.
- Further research is needed to address limitations in modeling three-level system interactions with control pulses.
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