Three-particle electron-hole complexes in two-dimensional electron systems

Abstract

Three-particle complexes consisting of two holes in the completely filled zero electron Landau level and an excited electron in the unoccupied first Landau level are investigated in a quantum Hall insulator. The distinctive features of these three-particle complexes are an electron-hole mass symmetry and the small energy gap of the quantum Hall insulator itself. Theoretical calculations of the trion energy spectrum in a quantizing magnetic field predict that, besides the ground state, trions feature a hierarchy of excited bound states. In agreement with the theoretical simulations, we observe new photoluminescence lines related to the excited trion states. A relatively small energy gap allows the binding of three-particle complexes with magnetoplasma oscillations and formation of plasmarons. The plasmaron properties are investigated experimentally.

The Local Incompressibility of Fractional Quantum Hall States at a Filling Factor of 3/2

“…The intensity of the trion line accounts for the whole density of the nonequilibrium excitations with ∆M = 1 and ∆S z = 1 in the excitation spot. Plasmaron photoluminescence contains information on the total number of excitations as well as on the plasmarons spec- tral density that yields, in turn, the density distribution of nonequilibrium excitations in the momentum space before they bind to the Fermi hole [29,31]. The model is only approximately valid for the fractional ground state.…”

Coherence of a Magnetoexciton Condensate in a Quantum Hall Insulator

“…Consequently, in addition to photoinduced resonant reflection of light, it is necessary to simultaneously detect PL spectra of the 2DES: they allow one to determine the generalized momentum distribution function of magnetoexcitons. When nonequilibrium excitations appear in the system, features associated with translationally invariant three-particle complexes formed by a dark triplet magnetoexciton and an additional Fermi hole appear in PL spectra [10,11] (see Fig. 1).…”

Local incompressibility of fractional quantum Hall states at a filling factor of 3/2

“…The intensity of the trion line accounts for the whole density of the nonequilibrium excitations with M = 1 and S z = 1 in the excitation spot. Plasmaron photoluminescence contains information on the total number of excitations as well as on the plasmarons spectral density that yields, in turn, the density distribution of nonequilibrium excitations in the momentum space before they bind to the Fermi hole [29,31]. The model is only approximately valid for the fractional ground state.…”

“…Such a relaxation process is impossible, for instance, at integer filling factor ν = 2, which reflects the incompressibility of the electron gas in the lowest energy spin sublevel of Landau level. This also leads to the formation of charged three-particle complexes (plasmarons and trions) [29,31].…”