Abstract
We theoretically describe the spin-excitation spectrum of a two-dimensional electron gas embedded in a quantum well with localized magnetic impurities. Compared to the previous work published in [Phys. Rev. B 70, 45205 (2004)] and [Phys. Rev. B 79, 045306 (2009)], we introduce equations that allow us to consider the interplay between the Coulomb interaction of delocalized electrons and the exchange coupling between electrons and magnetic impurities. Strong qualitative changes are found: mixed waves propagate below the single-particle continuum, an anticrossing gap is open at a specific wave vector, and the kinetic damping due to the electron motion [Phys. Rev. B 81, 100403 (2010)] strongly influences the coupling strength between electrons and impurities spins.
- Received 27 September 2010
DOI:https://doi.org/10.1103/PhysRevB.83.075311
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