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

The possibility of coherent population trapping in two electron states with aligned spins was shown. Appearance of a new kind of dark state was concluded by analysis of a three-level atomic system containing two electrons, and driven by two laser fields. The properties of trapping were interpreted in terms of a dark hole, instead of a dark, two electron state. The technique is applied in measurement of superposition-state matrix elements of the electron-electron correlation with subnatural resolution.