A ug 1 99 9 Oscillatory screening of the dc electric field in the Si - SiO 2 multiple quantum wells probed by second - harmonic generation
نویسندگان
چکیده
DC-electric field, being screened in 3D semiconductors, normally decays monotonically in space. Experimental studies of the DC electric field screening in Si-SiO 2 multiple quantum wells by electric field induced optical second-harmonic generation show a non-monotonic, oscillatory-like decay. The model of electrons localized inside quantum wells, with the first subband occupied, allows a description of the phenomenon. Interwell Coulomb interaction, a finite value of the electron charge and strong effective-mass anisotropy result in a crucial difference from 3D Fermi liquid.
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