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Updated: Jun 8, 2026

Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Observation of ground-state quantum beats in atomic spontaneous emission
D G Norris1, L A Orozco, P Barberis-Blostein
1Joint Quantum Institute, Department of Physics, University of Maryland and National Institute of Standards and Technology, College Park, Maryland 20742-4111, USA.
Abstract:
We report ground-state quantum beats in spontaneous emission from a continuously driven atomic ensemble. Beats are visible only in an intensity autocorrelation and evidence spontaneously generated coherence in radiative decay. Our measurement realizes a quantum eraser where a first photon detection prepares a superposition and a second erases the "which path" information in the intermediate state.
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