RAMAN-SCATTERING SPECTRA OF ELEMENTARY ELECTRONIC EXCITATIONS IN COUPLED DOUBLE-QUANTUM-WELL STRUCTURES

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关键词: GAS;    HETEROJUNCTIONS;    EXCHANGE;    SYSTEMS;   

DOI  :  10.1103/PhysRevB.49.16821

来源: SCIE

【 摘 要 】

Using the time-dependent local-density approximation (TDLDA) within a self-consistent linear-response theory, we calculate the elementary excitation energies and the associated inelastic light-scattering spectra of a strongly coupled two-component plasma in a double-quantum-well system with electron occupation of symmetric and antisymmetric subbands. We find, consistent with the results of a recent experimental Raman-scattering study, that the intersubband spin-density excitations tend to merge with the single-particle excitations (i.e., the excitonic shift decreases monotonically) as the Fermi energy increases beyond the symmetric-antisymmetric energy gap DELTA(SAS). However, our TDLDA calculation does not show the abrupt suppression of the excitonic shift seen experimentally at a finite value of the subband occupancy parameter eta = DELTA(SAS)/E(F).

【 授权许可】

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