Dynamical Corrections to Spin Wave Excitations in Quantum Wells due to Coulomb Interactions and Magnetic Ions

Abstract

We have measured dispersions of spin-flip waves and spin-flip single-particle excitations of a spin polarized two-dimensional electron gas in a CdMnTe quantum well using resonant Raman scattering. We find the energy of the spin-flip wave to be below the spin-flip single particle excitation continuum, a contradiction to the theory of spin waves in diluted magnetic semiconductors put forth in [Phys. Rev. B 70, 045205 (2004)]. We show that the inclusion of terms accounting for the Coulomb interaction between carriers in the spin wave propagator leads to an agreement with our experimental results. The dominant Coulomb contribution leads to an overall red shift of the mixed electron-Mn spin modes while the dynamical coupling between Mn ions results in a small blue shift. We provide a simulated model system which shows the reverse situation but at an extremely large magnetic field.

6 pages, 7 figures

References in corpus (5)

• Photo-induced precession of magnetization in ferromagnetic (Ga,Mn)As
• Light-Induced Magnetic Precession in (Ga,Mn)As Slabs: Hybrid Standing-Wave Damon-Eshbach Modes
• Spin polarized two-dimensional electron gas embedded in semimagnetic quantum well : ground state, spin responses, spin excitations, Raman spectrum
• Spin dynamics in (III,Mn)V ferromagnetic semiconductors: the role of correlations
• Measuring the spin polarization and Zeeman energy of a spin-polarized electron gas: Comparison between Raman scattering and photoluminescence

Cited by in corpus (4)

• Coulomb-driven organization and enhancement of spin-orbit fields in collective spin excitations
• Chirality and intrinsic dissipation of spin modes in two-dimensional electron liquids
• Theory of carrier-mediated magnonic superlattices
• Spin precession and spin waves in a chiral electron gas: beyond Larmor's theorem