Cyclotron spin-wave in the 2D electron system

The cyclotron spin-wave mode of a two-dimensional electron system have been investigated by inelastic light scattering. It is observed at small electron filling factors, $\nu \sim 0.1$, when the electron system is spin-depolarized. As long as the electron system becomes fully spin-polarized ($\nu > 0.2$) the cyclotron spin-wave disappears from the inelastic light scattering spectra. It reenters at electron filling factors $\nu > 1$. Over the range of electron filling factors of $1 < \nu < 2$ the cyclotron spin-wave energy is insensitive to both the experimentally accessible in-plane momenta and the electron concentration, whereas its inelastic light scattering efficiency is strongly influenced by the spin polarization of the electron system.