Collective Excitations of a Composite Fermion Gas in Fractional Quantum Hall Effect

Szu-Cheng Cheng

《Chinese Journal of Physics》 38卷2S期 (2000/04) Pp. 380-385

並列摘要

The equations-of-motion method is used to calculate excitation energies of a compositefermion gas in fractional quantum Hall effect. The gauge theory of composite fermions is applied in this study. Full gauge fluctuations, which contain two-body gauge interactions and three-body gauge interactions, are investigated. Comparing with excitations calculated by the random-phase approximation, collective-excitation spectra are changed dramatically by the three-body gauge interactions. In order that the gauge theory agrees with the finitesize studies, we find that the three-body gauge interactions are important in excitations of composite fermion gas. Both cases with and without Coulomb interactions are considered. Except the cyclotron energy, Coulomb interactions raise the gap energies at q = 0. Coulomb interactions have no effect on the cyclotron energy, in accordance with Kohn's theorem.