摘要:

AbstractA theory of the direct creation of excitonic molecules (biexcitons) by direct two‐photon absorption in semiconductor quantum well structures is developed. An analytical expression of the biexciton two‐photon absorption coefficient is given for both photon polarizations. Excitonic‐, interband‐two‐photon, and exciton one‐photon processes in quantum wells (QW) are also investigated. The analytical forms and numerical values of the momentum matrix elements involved in each process are provided. The biexciton matrix element is calculated adopting a six‐parameter variational wave function. A numerical estimation for GaAs QW shows that the biexciton two‐photon absorption (BTPA) process dominates the other processes by different orders of magnitude. This enhancement essentially comes from the resonance effect and the structure of the matrix elements included in each process. Furthermore, the BTPA process in the QW for both polarizations is enhanced over its bulk value by about four and five orders of magnitude. This increase is interpreted as due to the spatial confin

ISSN:0370-1972    

DOI:10.1002/pssb.2221810123

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY

ISSN:0370-1972    

DOI:10.1002/pssb.2221810101

出版商:WILEY‐VCH Verlag    

年代:1994

数据来源: WILEY