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arXiv · 1309.6098

Many-body corrections to ESR energy and spin-wave excitations in two-dimensional systems with Bychkov-Rashba spin splitting

Abstract

We report effects of electron-electron (\emph{e-e}) interaction on electron spin resonance (ESR) in perpendicular magnetic field in two-dimensional (2D) systems with Bychkov-Rashba spin splitting induced by spin-orbit interaction (SOI) and structural inversion asymmetry (SIA). Using the Hartree-Fock approximation, we demonstrate that the SIA results in non-zero many-body corrections to the ESR energy and the energy of spin wave excitations. We discover that the \emph{e-e} interaction in 2D systems with SIA not only can enhance the ESR energy but can also lead to the ESR energy reduction. The magnitude of this effect exhibits remarkable features in a wide range of parameters relevant to experiment: it is found to be rather sensitive to the sign of g-factor and the filling factor of Landau levels $ν$. We derive analytical expressions for many-body corrections to ESR energy and the dispersion of spin wave excitations for the case of $ν\leq 2$. We have found out that \emph{e-e} interaction does not affect the ESR energy in the case of filling of the lowest Landau level ($ν\leq 1$) in 2D systems with positive g-factors even at arbitrarily large values of Bychkov-Rashba constant. The many-body renormalization of ESR energy in the case of fractional Quantum Hall effect is also discussed.

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BibTeXRIS

S. S. Krishtopenko. 2013-09-24. Many-body corrections to ESR energy and spin-wave excitations in two-dimensional systems with Bychkov-Rashba spin splitting. https://doi.org/10.1088/0268-1242%2F29%2F8%2F085005

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