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Coherent population trapping in two-electron three-level systems with aligned spins

J. Mompart·R. Corbalan·L. Roso
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Abstract

The possibility of coherent population trapping in two electron states with aligned spins (ortho-system) is evidenced. From the analysis of a three-level atomic system containing two electrons, and driven by the two laser fields needed for coherent population trapping, a conceptually new kind of two-electron dark state appears. The properties of this trapping are studied and are physically interpreted in terms of a dark hole, instead of a dark two-electron state. This technique, among many other applications, offers the possibility of measuring, with subnatural resolution, some superposition-state matrix-elements of the electron-electron correlation that due to their time dependent nature are inaccesible by standard measuring procedures.

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J. Mompart, R. Corbalan, L. Roso. 2001-07-25. Coherent population trapping in two-electron three-level systems with aligned spins. https://doi.org/10.1103/physrevlett.88.023603

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