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arXiv · 1011.4422

Spin waves in magnetic quantum wells with Coulomb interaction and $sd$ exchange coupling

Florent Perez·Joel Cibert·Masha Vladimirova·Denis Scalbert
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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, we introduce equations that allow to consider the interplay between the Coulomb interaction of delocalized electrons and the $sd$ 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 wavevector and the kinetic damping due to the electron motion strongly influences the coupling strength between electrons and impurities spins.

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Florent Perez, Joel Cibert, Masha Vladimirova, Denis Scalbert. 2010-11-19. Spin waves in magnetic quantum wells with Coulomb interaction and $sd$ exchange coupling. https://doi.org/10.1103/physrevb.83.075311

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