Kulik, L. V. and Kukushkin, I. V. and Kirpichev, V. E. and Smet, J. H. and Klitzing, Klaus von and Wegscheider, Werner
Cyclotron spin-flip excitations in the extreme quantum limit.
Physical Review B 63 (20), 201402R.
The cyclotron spin-flip excitations of a two-dimensional electron system in the extreme quantum limit have been investigated by inelastic light scattering. The electron interaction energy was directly determined from the gap between the charge- and spin-density modes in a broad region of electron filling factors. A comparison of the experimental results with the Hartree-Fock and generalized single mode approximations indicates a strong correlation between electrons at filling factors corresponding to both compressible and incompressible states.