The optical behaviour of the absorption edge of thin GaAs crystals with the 'super-quantum' thickness

摘要

SThe optical absorption of pure GaAs samples with thickness d chemical bounds 0.3 / 4.4 mu m (l > d a_(exc), where a_(exc) is Bohr radius for exciton and l~* is exciton-olariton mean free path length) has been investigated at T chemical bounds 1.7K. Strong changes in the spectral behaviour of the absorption edge dur to surface electric field, ionization, excition line broadening and Stark shift on it, olariton light propagation witout real absorption, quantization of exciton as a whole and polariton wave interference have been observed.