SPATIAL CORRELATION OF AN ELECTRON AND HOLE IN QUASI-2-DIMENSIONAL ELECTRONIC SYSTEM IN A STRONG MAGNETIC-FIELD AND ITS RELATIONSHIP TO THELIGHT-SCATTERING TENSOR

The spatial correlation of light-generated electrons and holes in a qu asi-two-dimensional electron gas in a strong magnetic field is investi gated in an approximation linear in the intensity of the exciting ligh t. The correlation is due to the interaction of the electrons and hole s with longitudinal optical (LO) phonons. The theory permits calculati ng, on the basis of a special diagrammatic technique, two distribution functions of an electron-hole pair with respect to the distance betwe en the electron and the hole after the emission of N phonons: first, t he function determining the total number of pairs which have emitted N phonons and, second, the function related to the rank-4 light-scatter ing tensor in interband resonance Raman scattering of light. A special feature of the system is that the electron and hole energy levels are discrete. The calculation is performed for a square quantum well with infinitely high barriers. The distribution function and the total num ber of electron-hole pairs before the emission of phonons as well as t he distribution function corresponding to two-phonon resonance Raman s cattering are calculated. The theory predicts the appearance of severa l close-lying peaks in the excitation spectrum under resonance conditi ons. The number of peaks is related to the number of the Landau level participating in the optical transition. The distance between peaks is determined by the electron-phonon coupling constant. Far from resonan ce there is one peak, which is much weaker than the peaks obtained und er resonance conditions. (C) 1997 American Institute of Physics.