Radiation Problems in Quantum-Electronics for Degenerate Two-Level System.

Gerald F. Thomas, William J. Meath

S. D. Berry, C. Böttcher

William H. Louisell

Vladimir V. Likhanskii

Expressions are obtained for the probability of a nonadiabatic transition between two degenerate levels under the action of laser radiation with a continuously variable resonance frequency. It is shown that this problem reduces to the solution of the Landau–Zener problem for eigenvectors of the matrix of a transition between two degenerate levels.

Sophia E. Economou, Ren‐Bao Liu, Lu Jeu Sham +1 more

In a $\ensuremath{\Lambda}$ 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.

H.S. Zivi, ALFRED BAUDER, Hs. H. Günthard