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A Unified Theory of Consequences of Spontaneous Emission in a $Λ$ System

Sophia E. Economou·Ren-Bao Liu·L. J. Sham·D. G. Steel
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Abstract

In a $Λ$ system with two nearly degenerate ground states and one excited state in an atom or quantum dot, spontaneous radiative decay can lead to a range of phenomena, including electron-photon entanglement, spontaneously generated coherence, and two-pathway decay. We show that a treatment of the radiative decay as a quantum evolution of a single physical system composed of a three-level electron subsystem and photons leads to a range of consequences depending on the electron-photon interaction and the measurement. Different treatments of the emitted photon channel the electron-photon system into a variety of final states. The theory is not restricted to the three-level system.

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Sophia E. Economou, Ren-Bao Liu, L. J. Sham, D. G. Steel. 2005-01-19. A Unified Theory of Consequences of Spontaneous Emission in a $Λ$ System. https://doi.org/10.1103/physrevb.71.195327

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