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Theory of spin waves in diluted-magnetic-semiconductor quantum wells

Diego Frustaglia·Jürgen König·Allan H. MacDonald
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Abstract

We present a theory of collective spin excitations in diluted-magnetic-semiconductor quantum wells in which local magnetic moments are coupled via a quasi-two-dimensional gas of electrons or holes. In the case of a ferromagnetic state with partly spin-polarized electrons, we find that the Goldstone collective mode has anomalous $k^4$ dispersion and that for symmetric quantum wells odd parity modes do not disperse at all. We discuss the gap in the collective excitation spectrum which appears when spin-orbit interactions are included.

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Diego Frustaglia, Jürgen König, Allan H. MacDonald. 2004-03-19. Theory of spin waves in diluted-magnetic-semiconductor quantum wells. https://doi.org/10.1103/physrevb.70.045205

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