title: Spin-density response function in a 2D electron system under a magnetic field.
abstract: We study the spin density response function in a two-dimensional electron system under a strong perpendicular magnetic field. The theoretical framework is the extended RPA which takes into account all the second order self-energies of particle-hole propagators. Our results reproduce the data obtained by a light scattering experiment. We clarify how the extended RPA explains the empirical findings which are different even qualitatively from the RPA response. Especially the important role played by the two-particle-two-hole degrees of freedom is stressed.
authors.affiliation: Department of Physics, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Yoshizawa
authors.forename: Natsuko
authors.initials: N
authors.lastname: Hirano
authors.forename: Kazuo
authors.initials: K
authors.lastname: Takayanagi